diff --git a/collects/net/cgi.ss b/collects/net/cgi.rkt
similarity index 100%
rename from collects/net/cgi.ss
rename to collects/net/cgi.rkt
diff --git a/collects/net/cookie.ss b/collects/net/cookie.rkt
similarity index 100%
rename from collects/net/cookie.ss
rename to collects/net/cookie.rkt
diff --git a/collects/net/dns.ss b/collects/net/dns.rkt
similarity index 100%
rename from collects/net/dns.ss
rename to collects/net/dns.rkt
diff --git a/collects/net/ftp.ss b/collects/net/ftp.rkt
similarity index 100%
rename from collects/net/ftp.ss
rename to collects/net/ftp.rkt
diff --git a/collects/net/imap.ss b/collects/net/imap.rkt
similarity index 100%
rename from collects/net/imap.ss
rename to collects/net/imap.rkt
diff --git a/collects/net/mime-util.ss b/collects/net/mime-util.rkt
similarity index 100%
rename from collects/net/mime-util.ss
rename to collects/net/mime-util.rkt
diff --git a/collects/net/mime.ss b/collects/net/mime.rkt
similarity index 100%
rename from collects/net/mime.ss
rename to collects/net/mime.rkt
diff --git a/collects/net/nntp.ss b/collects/net/nntp.rkt
similarity index 100%
rename from collects/net/nntp.ss
rename to collects/net/nntp.rkt
diff --git a/collects/net/pop3.ss b/collects/net/pop3.rkt
similarity index 100%
rename from collects/net/pop3.ss
rename to collects/net/pop3.rkt
diff --git a/collects/net/private/rbtree.ss b/collects/net/private/rbtree.rkt
similarity index 100%
rename from collects/net/private/rbtree.ss
rename to collects/net/private/rbtree.rkt
diff --git a/collects/net/qp.ss b/collects/net/qp.rkt
similarity index 100%
rename from collects/net/qp.ss
rename to collects/net/qp.rkt
diff --git a/collects/net/scribblings/common.ss b/collects/net/scribblings/common.rkt
similarity index 100%
rename from collects/net/scribblings/common.ss
rename to collects/net/scribblings/common.rkt
diff --git a/collects/net/scribblings/info.ss b/collects/net/scribblings/info.rkt
similarity index 100%
rename from collects/net/scribblings/info.ss
rename to collects/net/scribblings/info.rkt
diff --git a/collects/net/scribblings/net.scrbl b/collects/net/scribblings/net.scrbl
index ca20926846..23128e0fda 100644
--- a/collects/net/scribblings/net.scrbl
+++ b/collects/net/scribblings/net.scrbl
@@ -1,7 +1,7 @@
 #lang scribble/doc
 @(require "common.ss")
 
-@title{@bold{Net}: PLT Networking Libraries}
+@title{@bold{Net}: Racket Networking Libraries}
 
 @table-of-contents[]
 
diff --git a/collects/net/scribblings/sendurl.scrbl b/collects/net/scribblings/sendurl.scrbl
index 96317df1fb..fc479dac3f 100644
--- a/collects/net/scribblings/sendurl.scrbl
+++ b/collects/net/scribblings/sendurl.scrbl
@@ -29,16 +29,18 @@ use an intermediate redirecting file due to a bug in IE7.)
 Under Mac OS X, @scheme[send-url] runs @exec{osascript} to start the
 user's chosen browser.
 
-Under Unix, @scheme[send-url] uses the value of the
-@scheme[external-browser] parameter to select a browser.
+Under Unix, @scheme[send-url] uses a user-preference, or when none is
+set, it will look for a known browser.  See the description of
+@scheme[external-browser] for details.
 
 The @scheme[url] string is usually escaped to avoid dangerous shell
-characters (quotations, dollar signs, backslashes, and non-ASCII).
-Note that it is a good idea to encode URLs before passing them to this
-function.  Also note that the encoding is meant to make the URL work
-in shell quotes: URLs can still hold characters like @litchar{#},
-@litchar{?}, and @litchar{&}, so the @scheme[external-browser] should
-use quotations.}
+characters (quotations, dollar signs, backslashes, and non-ASCII).  Note
+that it is a good idea to encode URLs before passing them to this
+function.
+
+On all platforms, @scheme[external-browser] parameter can be set to a
+procedure to override the above behavior --- the procedure will be
+called with the @scheme[url] string.}
 
 @defproc[(send-url/file [path path-string?] [separate-window? any/c #t]
                         [#:fragment fragment (or/c string? false/c) #f]
@@ -71,20 +73,24 @@ old temporary files are still deleted as described above.}
 
 @defparam[external-browser cmd browser-preference?]{
 
-A parameter that, under Unix, determines the browser started
-@scheme[send-url].
+A parameter that can hold a procedure to override how a browser is
+started, or @scheme[#f] to use the default platform-dependent command.
 
-The parameter is initialized to the value of the
-@scheme['external-browser] preference.
+Under Unix, the command that is used depends on the
+@scheme['external-browser] preference.  If the preference is unset,
+@scheme[send-url] uses the first of the browsers from
+@scheme[unix-browser-list] for which the executable is found.
+Otherwise, the preference should hold a symbol indicating a known
+browser (from the @scheme[unix-browser-list]), or it a pair of a prefix
+and a suffix string that are concatenated around the @scheme[url] string
+to make up a shell command to run.  In addition, the
+@scheme[external-browser] paremeter can be set to one of these values,
+and @scheme[send-url] will use it instead of the preference value.
 
-The parameter value can be any of the symbols in
-@scheme[unix-browser-list], @scheme[#f] to indicate that the
-preference is unset, or a pair of strings.  If the preference is
-unset, @scheme[send-url] uses the first of the browsers from
-@scheme[unix-browser-list] for which the executable is found. If the
-parameter is a pair of strings, then a command line is constructed by
-concatenating in order the first string, the URL string, and the
-second string.
+Note that the URL is encoded to make it work inside shell double-quotes:
+URLs can still hold characters like @litchar{#}, @litchar{?}, and
+@litchar{&}, so if the @scheme[external-browser] is set to a pair of
+prefix/suffix strings, they should use double quotes around the url.
 
 If the preferred or default browser can't be launched,
 @scheme[send-url] fails. See @scheme[get-preference] and
diff --git a/collects/net/scribblings/url.scrbl b/collects/net/scribblings/url.scrbl
index 56f6e2af0c..bbdcbb90f9 100644
--- a/collects/net/scribblings/url.scrbl
+++ b/collects/net/scribblings/url.scrbl
@@ -69,9 +69,9 @@ adjusts the behavior.
 
 An empty string at the end of the @scheme[path] list corresponds to a
 URL that ends in a slash. For example, the result of
-@scheme[(string->url "http://www.drscheme.org/a/")] has a
+@scheme[(string->url "http://racket-lang.org/a/")] has a
 @scheme[path] field with strings @scheme["a"] and @scheme[""], while
-the result of @scheme[(string->url "http://www.drscheme.org/a")] has a
+the result of @scheme[(string->url "http://racket-lang.org/a")] has a
 @scheme[path] field with only the string @scheme["a"].
 
 When a @scheme["file"] URL is represented by a @scheme[url] structure,
diff --git a/collects/net/sendmail.ss b/collects/net/sendmail.rkt
similarity index 100%
rename from collects/net/sendmail.ss
rename to collects/net/sendmail.rkt
diff --git a/collects/net/sendurl.ss b/collects/net/sendurl.rkt
similarity index 100%
rename from collects/net/sendurl.ss
rename to collects/net/sendurl.rkt
diff --git a/collects/net/smtp.ss b/collects/net/smtp.rkt
similarity index 100%
rename from collects/net/smtp.ss
rename to collects/net/smtp.rkt
diff --git a/collects/net/ssl-tcp-unit.ss b/collects/net/ssl-tcp-unit.rkt
similarity index 100%
rename from collects/net/ssl-tcp-unit.ss
rename to collects/net/ssl-tcp-unit.rkt
diff --git a/collects/net/tcp-redirect.ss b/collects/net/tcp-redirect.rkt
similarity index 100%
rename from collects/net/tcp-redirect.ss
rename to collects/net/tcp-redirect.rkt
diff --git a/collects/net/tcp-sig.ss b/collects/net/tcp-sig.rkt
similarity index 100%
rename from collects/net/tcp-sig.ss
rename to collects/net/tcp-sig.rkt
diff --git a/collects/net/tcp-unit.ss b/collects/net/tcp-unit.rkt
similarity index 100%
rename from collects/net/tcp-unit.ss
rename to collects/net/tcp-unit.rkt
diff --git a/collects/net/unihead.ss b/collects/net/unihead.rkt
similarity index 100%
rename from collects/net/unihead.ss
rename to collects/net/unihead.rkt
diff --git a/collects/tests/net/cgi.ss b/collects/tests/net/cgi.rkt
similarity index 100%
rename from collects/tests/net/cgi.ss
rename to collects/tests/net/cgi.rkt
diff --git a/collects/tests/net/cookie.ss b/collects/tests/net/cookie.rkt
similarity index 92%
rename from collects/tests/net/cookie.ss
rename to collects/tests/net/cookie.rkt
index 601eb3d71f..57200a5927 100644
--- a/collects/tests/net/cookie.ss
+++ b/collects/tests/net/cookie.rkt
@@ -19,12 +19,12 @@
     (syntax-rules ()
       [(o/* x) x]
       [(o/* x f g ...) (f (o/* x g ...))]))
-
+  
   (define (tests)
-
+    
     ;; test the most basic functionality
     (cookie-test (λ (x) x) "a=b; Version=1")
-
+    
     ;; test each modifier individually
     (cookie-test (RC cookie:add-comment "set+a+to+b")
                  "a=b; Comment=set+a+to+b; Version=1")
@@ -54,7 +54,7 @@
                  "a=b; Version=1")
     (cookie-test (RC cookie:version 12)
                  "a=b; Version=12")
-
+    
     ;; test combinations
     (cookie-test (o (RC cookie:add-comment "set+a+to+b")
                     (RC cookie:add-domain ".example.net"))
@@ -66,7 +66,7 @@
                     (RC cookie:version 10)
                     (RC cookie:add-max-age 20))
                  "a=b; Max-Age=20; Path=\"/whatever/wherever/\"; Version=10")
-
+    
     ;; test error cases
     (let ()
       (define-syntax cookie-error-test
@@ -78,7 +78,18 @@
       (cookie-error-test (RC cookie:add-domain "doesntstartwithadot.example.com"))
       (cookie-error-test (RC cookie:add-domain "bad domain.com"))
       (cookie-error-test (RC cookie:add-domain ".bad-domain;com")))
-
+    
+    ; cookie value
+    (test
+     (cookie-value? "value")
+     (cookie-value? "(")
+     (cookie-value? "!")
+     (cookie-value? ")")
+     (cookie-value? ")!")
+     (cookie-value? "(!")
+     (cookie-value? "(!)")
+     (cookie-value? "!)"))
+    
     )
-
+  
   (test do (tests)))
diff --git a/collects/tests/net/encoders.ss b/collects/tests/net/encoders.rkt
similarity index 95%
rename from collects/tests/net/encoders.ss
rename to collects/tests/net/encoders.rkt
index 3d06130db2..43f77399d7 100644
--- a/collects/tests/net/encoders.ss
+++ b/collects/tests/net/encoders.rkt
@@ -2,7 +2,7 @@
 (require net/base64 net/qp tests/eli-tester)
 
 (define tricky-strings
-  (let ([dir (collection-path "tests" "mzscheme")])
+  (let ([dir (collection-path "tests" "racket")])
     (list (make-bytes 200 32)
           (make-bytes 200 9)
           (make-bytes 200 (char->integer #\x))
@@ -12,12 +12,12 @@
           (make-bytes 204 (char->integer #\x))
           (list->bytes (for/list ([i (in-range 256)]) i))
           ;; Something that doesn't end with a LF:
-          (bytes-append (with-input-from-file (build-path dir "net.ss")
+          (bytes-append (with-input-from-file (build-path dir "net.rktl")
                           (lambda () (read-bytes 500)))
            #"xxx")
           ;; CRLF:
           (regexp-replace #rx#"\r?\n"
-                          (with-input-from-file (build-path dir "net.ss")
+                          (with-input-from-file (build-path dir "net.rktl")
                             (lambda () (read-bytes 500)))
            #"\r\n"))))
 
@@ -55,13 +55,13 @@
                           (open-input-bytes tricky-string)
                           line-rx max-w))
             tricky-strings)
-  (let* ([dir (collection-path "tests" "mzscheme")]
+  (let* ([dir (collection-path "tests" "racket")]
          [files (filter-map
                  (lambda (f)
                    ;; check 1/4 of the files, randomly
                    (let ([p (build-path dir f)])
                      (and (zero? (random 4))
-                          (not (regexp-match #rx"^flat.*\\.ss$"
+                          (not (regexp-match #rx"^flat.*\\.rktl$"
                                              (path-element->string f)))
                           (file-exists? p)
                           p)))
diff --git a/collects/tests/net/head.ss b/collects/tests/net/head.rkt
similarity index 100%
rename from collects/tests/net/head.ss
rename to collects/tests/net/head.rkt
diff --git a/collects/tests/net/main.ss b/collects/tests/net/main.rkt
similarity index 100%
rename from collects/tests/net/main.ss
rename to collects/tests/net/main.rkt
diff --git a/collects/tests/net/uri-codec.ss b/collects/tests/net/uri-codec.rkt
similarity index 100%
rename from collects/tests/net/uri-codec.ss
rename to collects/tests/net/uri-codec.rkt
diff --git a/collects/tests/net/url.ss b/collects/tests/net/url.rkt
similarity index 99%
rename from collects/tests/net/url.ss
rename to collects/tests/net/url.rkt
index e6b52ef462..1817082d4b 100644
--- a/collects/tests/net/url.ss
+++ b/collects/tests/net/url.rkt
@@ -228,8 +228,8 @@
          "HTTP://ROBBY@WWW.DRSCHEME.ORG:80/INDEX.HTML;XXX?T=P#YYY")
         => #("http" "ROBBY" "www.drscheme.org" 80 #t (#("INDEX.HTML" "XXX")) ((T . "P")) "YYY"))
 
-  (test-s->u #("mailto" #f #f #f #f (#("robby@plt-scheme.org")) () #f)
-             "mailto:robby@plt-scheme.org")
+  (test-s->u #("mailto" #f #f #f #f (#("robby@racket-lang.org")) () #f)
+             "mailto:robby@racket-lang.org")
 
   (test (string->url/vec "http://www.drscheme.org?bar=馨慧")
         #("http" #f "www.drscheme.org" #f #f () ((bar . "馨慧")) #f))
diff --git a/collects/tests/mzscheme/net.ss b/collects/tests/racket/net.rktl
similarity index 84%
rename from collects/tests/mzscheme/net.ss
rename to collects/tests/racket/net.rktl
index 5d804c56e0..9b86f927f5 100644
--- a/collects/tests/mzscheme/net.ss
+++ b/collects/tests/racket/net.rktl
@@ -1,5 +1,5 @@
 
-(load-relative "loadtest.ss")
+(load-relative "loadtest.rktl")
 
 (Section 'net)