diff --git a/collects/net/scribblings/dns.scrbl b/collects/net/scribblings/dns.scrbl
new file mode 100644
index 0000000000..b586f983b2
--- /dev/null
+++ b/collects/net/scribblings/dns.scrbl
@@ -0,0 +1,76 @@
+#lang scribble/doc
+@(require "common.ss"
+          (for-label net/dns
+                     net/dns-unit
+                     net/dns-sig))
+
+@title{DNS: Domain Name Service Queries}
+
+@defmodule[net/dns]{The @schememodname[net/dns] module provides
+utilities for looking up hostnames.
+
+Thanks to Eduardo Cavazos and Jason Crowe for repairs and
+improvements.}
+
+@; ----------------------------------------
+
+@section[#:tag "dns-proc"]{Functions}
+
+@defproc[(dns-get-address [nameserver string?]
+                          [address string?])
+         string?]{
+
+Consults the specified nameserver (normally a numerical address like
+@scheme["128.42.1.30"]) to obtain a numerical address for the given
+Internet address.
+
+The query record sent to the DNS server includes the "recursive" bit,
+but @scheme[dns-get-address] also implements a recursive search itself
+in case the server does not provide this optional feature.}
+
+
+@defproc[(dns-get-name [nameserver string?]
+                       [address string?])
+         string?]{
+
+Consults the specified nameserver (normally a numerical address like
+@scheme["128.42.1.30"]) to obtain a name for the given numerical
+address.}
+
+
+@defproc[(dns-get-mail-exchanger [nameserver string?]
+                                 [address string?])
+         string?]{
+
+Consults the specified nameserver to obtain the address for a mail
+exchanger the given mail host address. For example, the mail exchanger
+for @scheme["ollie.cs.rice.edu"] might be @scheme["cs.rice.edu"].}
+
+
+
+@defproc[(dns-find-nameserver) (or/c string? false/c)]{
+
+Attempts to find the address of a nameserver on the present system.
+Under Unix, this procedure parses @filepath{/etc/resolv.conf} to
+extract the first nameserver address. Under Windows, it runs
+@exec{nslookup.exe}.}
+
+@; ----------------------------------------
+
+@section{DNS Unit}
+
+@defmodule[net/dns-unit]
+
+@defthing[dns@ unit?]{
+
+Imports nothing, exports @scheme[dns^].}
+
+@; ----------------------------------------
+
+@section{DNS Signature}
+
+@defmodule[net/dns-sig]
+
+@defsignature[dns^ ()]{}
+
+Includes everything exported by the @schememodname[net/dns] module.
diff --git a/collects/net/scribblings/head.scrbl b/collects/net/scribblings/head.scrbl
new file mode 100644
index 0000000000..9a17add642
--- /dev/null
+++ b/collects/net/scribblings/head.scrbl
@@ -0,0 +1,239 @@
+#lang scribble/doc
+@(require "common.ss"
+          scribble/eval
+          scribble/struct
+          (for-label net/head
+                     net/head-unit
+                     net/head-sig))
+
+@(define head-eval (make-base-eval))
+@interaction-eval[#:eval head-eval (require net/head)]
+
+@title{headers: Parsing and Constructing}
+
+@defmodule[net/head]{The @schememodname[net/head] module provides
+utilities for parsing and constructing RFC 822 headers
+@cite["RFC822"], which are used in protocols such as HTTP, SMTP, and
+NNTP.}
+
+A @deftech{header} is represented as a string or byte string
+containing CRLF-delimited lines. Each field within the header spans
+one or more lines. In addition, the header ends with two CRLFs
+(because the first one terminates the last field, and the second
+terminates the header).
+
+@; ----------------------------------------
+
+@section{Functions}
+
+@defthing[empty-header string?]{
+
+The string @scheme["\r\n\r\n"], which corresponds to the empty header.
+This value is useful for building up headers with
+@scheme[insert-field] and @scheme[append-headers].}
+
+
+@defproc[(validate-header [candidate (or string? bytes?)]) void?]{
+
+Checks that @scheme[candidate] matches RFC 822. If it does not, an
+exception is raised.}
+
+
+@defproc[(extract-field [field (or/c string? bytes?)] [header (or/c string? bytes?)])
+         (or/c string? bytes? false/c)]{
+
+Returns the header content for the specified field, or @scheme[#f] if
+the field is not in the header. The @scheme[field] string should not
+end with @scheme[":"], and it is used case-insensitively. The returned
+string will not contain the field name, color separator, or CRLF
+terminator for the field; however, if the field spans multiple lines,
+the CRLFs separating the lines will be intact.
+
+The @scheme[field] and @scheme[header] arguments must be both strings
+or both byte strings, and the result (if not @scheme[#f]) is of the
+same type.
+
+@examples[
+#:eval head-eval
+(extract-field "TO" (insert-field "to" "me@localhost" 
+                                  empty-header))
+]}
+
+@defproc[(extract-all-fields [header (or/c string? bytes?)])
+         (listof (cons/c (or/c string? bytes?)
+                         (or/c string? bytes?)))]{
+
+Returns an association-list version of the header; the case of the
+field names is preserved, as well as the order and duplicate uses of a
+field name.
+
+The result provides strings if @scheme[header] is a string, byte
+strings if @scheme[header] is a byte string.}
+
+
+@defproc[(remove-field [field (or/c string? bytes?)]
+                       [header (or/c string? bytes?)])
+          (or/c string? bytes?)]{
+
+Creates a new header by removing the specified field from
+@scheme[header] (or the first instance of the field, if it occurs
+multiple times). If the field is not in @scheme[header], then the
+return value is @scheme[header].
+
+The @scheme[field] and @scheme[header] arguments must be both strings
+or both byte strings, and the result is of the same type.}
+
+
+@defproc[(insert-field [field (or/c string? bytes?)]
+                       [value (or/c string? bytes?)]
+                       [header (or/c string? bytes?)])
+          (or/c string? bytes?)]{
+
+Creates a new header by prefixing the given @scheme[header] with the
+given @scheme[field]-@scheme[value] pair. The @scheme[value] string
+should not contain a terminating CRLF, but a multi-line value (perhaps
+created with @scheme[data-lines->data]) may contain separator CRLFs.
+
+The @scheme[field], @scheme[value], and @scheme[header] arguments must
+be all strings or all byte strings, and the result is of the same
+type.}
+
+
+@defproc[(replaces-field [field (or/c string? bytes?)]
+                         [value (or/c string? bytes? false/c)]
+                         [header (or/c string? bytes?)])
+          (or/c string? bytes?)]{
+
+Composes @scheme[remove-field] and (if @scheme[value] is not
+@scheme[#f]) @scheme[insert-field].}
+
+@defproc[(append-headers [header1 (or/c string? bytes?)]
+                         [header2 (or/c string? bytes?)])
+          (or/c string? bytes?)]{
+
+Appends two headers.
+
+The @scheme[header1] and @scheme[header2] arguments must be both
+strings or both byte strings, and the result is of the same type.}
+
+
+@defproc[(standard-message-header [from string?]
+                                  [to (listof -string?)]
+                                  [cc (listof strings?)]
+                                  [bcc (listof string?)]
+                                  [subject string?])
+          string?]{
+
+Creates a standard mail header given the sender, various lists of
+recipients, a subject. A @scheme["Date"] field is added to the header
+automatically, using the current time.
+
+The BCC recipients do not actually appear in the header, but they're
+accepted anyway to complete the abstraction.}
+
+
+@defproc[(data-lines->data (listof string?)) string?]{
+
+Merges multiple lines for a single field value into one string,
+adding CRLF-TAB separators.}
+
+
+@defproc[(extract-addresses [line string?]
+                            [kind (one-of/c 'name 'address
+                                            'full 'all)])
+          (or/c (listof string?)
+                (listof (list/c string? string? string?)))]{
+
+Parses @scheme[string] as a list of comma-delimited mail addresses,
+raising an exception if the list is ill-formed. This procedure can be
+used for single-address strings, in which case the returned list
+contains only one address.
+
+The @scheme[kind] argument specifies which portion of an address
+should be returned:
+
+@itemize[
+
+ @item{@scheme['name] --- the free-form name in the address, or the
+       address itself if no name is available.
+
+       @examples[
+       #:eval head-eval
+       (extract-addresses "John Doe <doe@localhost>" 'name)
+       (extract-addresses "doe@localhost (Johnny Doe)" 'name)
+       (extract-addresses "doe@localhost" 'name)
+       (extract-addresses " \"Doe, John\" <doe@localhost>, jane"
+                          'name)
+       ]}
+
+ @item{@scheme['address] --- just the mailing address, without any free-form
+               names.
+
+       @examples[
+       #:eval head-eval
+       (extract-addresses "John Doe <doe@localhost>" 'address)
+       (extract-addresses "doe@localhost (Johnny Doe)" 'address)
+       (extract-addresses "doe@localhost" 'address)
+       (extract-addresses " \"Doe, John\" <doe@localhost>, jane"
+                          'address)
+       ]}
+
+ @item{@scheme['full] --- the full address, essentially as it appears in the
+       input, but normalized.
+
+       @examples[
+       #:eval head-eval
+       (extract-addresses "John Doe   < doe@localhost >" 'full)
+       (extract-addresses "  doe@localhost  (Johnny Doe)" 'full)
+       (extract-addresses "doe@localhost" 'full)
+       (extract-addresses " \"Doe, John\" <doe@localhost>, jane"
+                          'full)
+       ]}
+
+ @item{@scheme['all] --- a list containing each of the three possibilities:
+              free-form name, address, and full address (in that
+              order).
+
+       @examples[
+       #:eval head-eval
+       (extract-addresses "John Doe <doe@localhost>" 'all)
+       (extract-addresses "doe@localhost (Johnny Doe)" 'all)
+       (extract-addresses "doe@localhost" 'all)
+       (extract-addresses " \"Doe, John\" <doe@localhost>, jane"
+                          'all)
+       ]}
+
+]}
+
+
+@defproc[(assemble-address-field (addrs (listof string?))) string?]{
+
+Creates a header field value from a list of addresses. The addresses
+are comma-separated, and possibly broken into multiple lines.
+
+@examples[
+#:eval head-eval
+(assemble-address-field '("doe@localhost" 
+                          "Jane <jane@elsewhere>"))
+]}
+
+
+@; ----------------------------------------
+
+@section{Header Unit}
+
+@defmodule[net/head-unit]
+
+@defthing[head@ unit?]{
+
+Imports nothing, exports @scheme[head^].}
+
+@; ----------------------------------------
+
+@section{Header Signature}
+
+@defmodule[net/head-sig]
+
+@defsignature[head^ ()]{}
+
+Includes everything exported by the @schememodname[net/head] module.
diff --git a/collects/net/scribblings/imap.scrbl b/collects/net/scribblings/imap.scrbl
index 9e2c24acc4..1ffeee1ed1 100644
--- a/collects/net/scribblings/imap.scrbl
+++ b/collects/net/scribblings/imap.scrbl
@@ -43,9 +43,9 @@
 
 @title{IMAP: Reading Mail}
 
-@defmodule[net/imap]{The @schememodname[net/imap] module provides for
-the client side of Internet Message Access Protocol version 4rev1
-@cite["RFC2060"].}
+@defmodule[net/imap]{The @schememodname[net/imap] module provides
+utilities for the client side of Internet Message Access Protocol
+version 4rev1 @cite["RFC2060"].}
 
 @; ----------------------------------------
 
@@ -497,3 +497,22 @@ mailbox path names.}
 Returns a list of IMAP flags for the given mailbox. See also
 @scheme[imap-flag->symbol].}
 
+@; ----------------------------------------
+
+@section{IMAP Unit}
+
+@defmodule[net/imap-unit]
+
+@defthing[imap@ unit?]{
+
+Imports nothing, exports @scheme[imap^].}
+
+@; ----------------------------------------
+
+@section{IMAP Signature}
+
+@defmodule[net/imap-sig]
+
+@defsignature[imap^ ()]{}
+
+Includes everything exported by the @schememodname[net/imap] module.
diff --git a/collects/net/scribblings/net.scrbl b/collects/net/scribblings/net.scrbl
index 4262bebaec..4be7c90bc5 100644
--- a/collects/net/scribblings/net.scrbl
+++ b/collects/net/scribblings/net.scrbl
@@ -6,13 +6,16 @@
 @table-of-contents[]
 
 @include-section["url.scrbl"]
+@include-section["uri-codec.scrbl"]
 @include-section["sendurl.scrbl"]
 @include-section["smtp.scrbl"]
 @include-section["cgi.scrbl"]
 @include-section["sendmail.scrbl"]
+@include-section["head.scrbl"]
 @include-section["nntp.scrbl"]
 @include-section["pop3.scrbl"]
 @include-section["imap.scrbl"]
+@include-section["dns.scrbl"]
 @include-section["gifwrite.scrbl"]
 
 @(bibliography
@@ -21,6 +24,13 @@
             #:title "Common Gateway Interface (CGI/1.1)"
             #:url "http://hoohoo.ncsa.uiuc.edu/cgi/")
 
+ (bib-entry #:key "RFC822"
+            #:title "Standard for the Format of ARPA Internet Text Messages"
+            #:author "David Crocker"
+            #:location "RFC"
+            #:url "http://www.ietf.org/rfc/rfc0822.txt"
+            #:date "1982")
+            
  (bib-entry #:key "RFC977"
             #:title "Network News Transfer Protocol"
             #:author "Brian Kantor and Phil Lapsley"
@@ -28,6 +38,13 @@
             #:url "http://www.ietf.org/rfc/rfc0977.txt"
             #:date "1986")
             
+ (bib-entry #:key "RFC1738"
+            #:title "Uniform Resource Locators (URL)"
+            #:author "T. Berners-Lee, L. Masinter, and M. McCahill"
+            #:location "RFC"
+            #:url "http://www.ietf.org/rfc/rfc1738.txt"
+            #:date "1994")
+
  (bib-entry #:key "RFC1939"
             #:title "Post Office Protocol - Version 3"
             #:author "J. Myers and M. Rose"
diff --git a/collects/net/scribblings/uri-codec.scrbl b/collects/net/scribblings/uri-codec.scrbl
new file mode 100644
index 0000000000..a8a6b9a229
--- /dev/null
+++ b/collects/net/scribblings/uri-codec.scrbl
@@ -0,0 +1,147 @@
+#lang scribble/doc
+@(require "common.ss"
+          scribble/bnf
+          scribble/eval
+          (for-label net/url
+                     net/uri-codec
+                     net/uri-codec-unit
+                     net/uri-codec-sig))
+
+@(define uri-codec-eval (make-base-eval))
+@interaction-eval[#:eval uri-codec-eval (require net/uri-codec)]
+
+@title{URI Codec: Encoding and Decoding URIs}
+
+@defmodule[net/uri-codec]{The @schememodname[net/uri-codec] module
+provides utilities for encoding and decoding strings using the URI
+encoding rules given in RFC 2396 @cite["RFC2396"], and to encode and
+decode name/value pairs using the
+@tt{application/x-www-form-urlencoded} mimetype given the in HTML 4.0
+specification.  There are minor differences between the two encodings.}
+
+The URI encoding uses allows a few characters to be represented as-is:
+@litchar{a} through @litchar{z}, @litchar{A} through @litchar{Z},
+@litchar{0}-@litchar{9}, @litchar{-}, @litchar{_}, @litchar{.},
+@litchar{!}, @litchar{~}, @litchar{*}, @litchar{'}, @litchar{(} and
+@litchar{)}.  The remaining characters are encoded as
+@litchar{%}@nonterm{xx}, where @nonterm{xx} is the two-character hex
+representation of the integer value of the character (where the
+mapping character--integer is determined by US-ASCII if the integer is
+less than 128).
+
+The encoding, in line with RFC 2396's recommendation, represents a
+character as-is, if possible.  The decoding allows any characters
+to be represented by their hex values, and allows characters to be
+incorrectly represented as-is.
+
+The rules for the @tt{application/x-www-form-urlencoded} mimetype
+given in the HTML 4.0 spec are:
+
+@itemize[
+
+  @item{Control names and values are escaped. Space characters are
+  replaced by @litchar{+}, and then reserved characters are escaped as
+  described in RFC 1738, section 2.2: Non-alphanumeric characters are
+  replaced by @litchar{%}@nonterm{xx} representing the ASCII code of
+  the character. Line breaks are represented as CRLF pairs:
+  @litchar{%0D%0A}. Note that RFC 2396 supersedes RFC 1738
+  @cite["RFC1738"].}
+
+  @item{The control names/values are listed in the order they appear
+  in the document. The name is separated from the value by @litchar{=}
+  and name/value pairs are separated from each other by either
+  @litchar{;} or @litchar{&}.  When encoding, @litchar{;} is used as
+  the separator by default. When decoding, both @litchar{;} and
+  @litchar{&} are parsed as separators by default.}
+
+]
+
+These rules differs slightly from the straight encoding in RFC 2396 in
+that @litchar{+} is allowed, and it represents a space.  The
+@schememodname[net/uri-codec] library follows this convention,
+encoding a space as @litchar{+} and decoding @litchar{+} as a space.
+In addtion, since there appear to be some brain-dead decoders on the
+web, the library also encodes @litchar{!}, @litchar{~}, @litchar{'},
+@litchar{(}, and @litchar{)} using their hex representation, which is
+the same choice as made by the Java's @tt{URLEncoder}.
+
+@; ----------------------------------------
+
+@section[#:tag "uri-codec-proc"]{Functions}
+
+@defproc[(uri-encode [str string?]) string?]{
+
+Encode a string using the URI encoding rules.}
+
+
+@defproc[(uri-decode [str string?]) string?]{
+
+Decode a string using the URI decoding rules.}
+
+
+@defproc[(form-urlencoded-encode [str string?]) string?]{
+
+Encode a string using the @tt{application/x-www-form-urlencoded}
+encoding rules. The result string contains no non-ASCII characters.}
+
+
+@defproc[(form-urlencoded-deecode [str string?]) string?]{
+
+Decode a string encoded using the
+@tt{application/x-www-form-urlencoded} encoding rules.}
+
+
+@defproc[(alist->form-urlencoded [alist (listof (cons/c symbol? string?))])
+         string?]{
+
+Encode an association list using the
+@tt{application/x-www-form-urlencoded} encoding rules.
+
+The @scheme[current-alist-separator-mode] parameter determines the
+separator used in the result.}
+
+
+@defproc[(form-urlencoded->alist [str string])
+         (listof (cons/c symbol? string?))]{
+
+Decode a string encoded using the
+@tt{application/x-www-form-urlencoded} encoding rules into an
+association list. All keys are case-folded for conversion to symbols.
+
+The @scheme[current-alist-separator-mode] parameter determines the way
+that separators are parsed in the input.}
+
+
+@defparam[current-alist-separator-mode mode 
+          (one-of/c 'amp 'semi 'amp-or-semi 'semi-or-amp)]{
+
+A parameter that determines the separator used/recognized between
+associations in @scheme[form-urlencoded->alist],
+@scheme[alist->form-urlencoded], @scheme[url->string], and
+@scheme[string->url].
+
+The default value is @scheme['amp-or-semi], which means that both
+@litchar{&} and @litchar{;} are treated as separators when parsing,
+and @litchar{&} is used as a separator when encoding. The other modes
+use/recognize only of the separators.
+
+@examples[
+#:eval uri-codec-eval
+(define ex '((x . "foo") (y . "bar") (z . "baz")))
+(code:line (current-alist-separator-mode 'amp) (code:comment #, @t{try @scheme['amp]...}))
+(form-urlencoded->alist "x=foo&y=bar&z=baz")
+(form-urlencoded->alist "x=foo;y=bar;z=baz")
+(alist->form-urlencoded ex)
+(code:line (current-alist-separator-mode 'semi) (code:comment #, @t{try @scheme['semi]...}))
+(form-urlencoded->alist "x=foo;y=bar;z=baz")
+(form-urlencoded->alist "x=foo&y=bar&z=baz")
+(alist->form-urlencoded ex)
+(code:line (current-alist-separator-mode 'amp-or-semi) (code:comment #, @t{try @scheme['amp-or-semi]...}))
+(form-urlencoded->alist "x=foo&y=bar&z=baz")
+(form-urlencoded->alist "x=foo;y=bar;z=baz")
+(alist->form-urlencoded ex)
+(code:line (current-alist-separator-mode 'semi-or-amp) (code:comment #, @t{try @scheme['semi-or-amp]...}))
+(form-urlencoded->alist "x=foo&y=bar&z=baz")
+(form-urlencoded->alist "x=foo;y=bar;z=baz")
+(alist->form-urlencoded ex)
+]}
diff --git a/collects/net/scribblings/url.scrbl b/collects/net/scribblings/url.scrbl
index f0aa400672..0317f38c0f 100644
--- a/collects/net/scribblings/url.scrbl
+++ b/collects/net/scribblings/url.scrbl
@@ -22,8 +22,7 @@ you have a regular input port with which to process the document, as with
 any other file. 
 
 Currently the only supported protocols are @scheme["http"] and
-sometimes @scheme["file"]. See also the @schememodname[net/news]
-library.
+sometimes @scheme["file"].
 
 @section{URL Structure}
 
@@ -284,7 +283,7 @@ something like @litchar{1.0} or @litchar{1.1}, @nonterm{code} is an
 exact integer for the response code, and @nonterm{message} is
 arbitrary text without a return or newline.
 
-The @schememodname[net/head.ss] library provides procedures, such as
+The @schememodname[net/head] library provides procedures, such as
 @scheme[extract-field] for manipulating the header.
 
 Since web servers sometimes return mis-formatted replies,
diff --git a/collects/scribblings/reference/breaks.scrbl b/collects/scribblings/reference/breaks.scrbl
index b54ea64553..e89776049b 100644
--- a/collects/scribblings/reference/breaks.scrbl
+++ b/collects/scribblings/reference/breaks.scrbl
@@ -76,7 +76,7 @@ exception is raised, but not both.  Scheme therefore supplies
 which does permit the implementation of such an exclusive guarantee:
 
 @schemeblock[
-(parameterize ([break-enabled #f])
+(parameterize-break #f
   (with-handlers ([exn:break? (lambda (x) (void))])
     (semaphore-wait/enable-break s)))
 ]