diff --git a/collects/net/cgi.ss b/collects/net/cgi.ss
index db770679d9..317331028c 100644
--- a/collects/net/cgi.ss
+++ b/collects/net/cgi.ss
@@ -1,8 +1,11 @@
 
-(require-library "cgiu.ss" "net")
+(module cgi mzscheme
+  (require (lib "unitsig.ss"))
 
-(begin-elaboration-time
- (require-library "invoke.ss"))
+  (require "cgi-sig.ss")
+  (require "cgi-unit.ss")
 
-(define-values/invoke-unit/sig mzlib:cgi^
-  mzlib:cgi@)
+  (define-values/invoke-unit/sig net:cgi^
+    net:cgi@)
+
+  (provide-signature-elements net:cgi^))
diff --git a/collects/net/dns.ss b/collects/net/dns.ss
index b569eb6866..44ad9cda6c 100644
--- a/collects/net/dns.ss
+++ b/collects/net/dns.ss
@@ -1,8 +1,11 @@
 
-(require-relative-library "dnss.ss")
+(module dns mzscheme
+  (require (lib "unitsig.ss"))
 
-(begin-elaboration-time
- (require-library "invoke.ss"))
+  (require "dns-sig.ss")
+  (require "dns-unit.ss")
 
-(define-values/invoke-unit/sig mzlib:dns^
-  (require-relative-library "dnsr.ss"))
+  (define-values/invoke-unit/sig net:dns^
+    net:dns@)
+
+  (provide-signature-elements net:dns^))
diff --git a/collects/net/nntp.ss b/collects/net/nntp.ss
index 0050f26a6d..57b2b25c4d 100644
--- a/collects/net/nntp.ss
+++ b/collects/net/nntp.ss
@@ -1,8 +1,11 @@
-(require-library "nntpu.ss" "net")
 
-(begin-elaboration-time
- (require-library "invoke.ss"))
+(module nntp mzscheme
+  (require (lib "unitsig.ss"))
 
-(define-values/invoke-unit/sig mzlib:nntp^
-  mzlib:nntp@
-  nntp)
+  (require "nntp-sig.ss")
+  (require "nntp-unit.ss")
+
+  (define-values/invoke-unit/sig net:nntp^
+    net:nntp@)
+
+  (provide-signature-elements net:nntp^))
diff --git a/collects/net/pop3.ss b/collects/net/pop3.ss
index b91822c818..1e30c920ce 100644
--- a/collects/net/pop3.ss
+++ b/collects/net/pop3.ss
@@ -1,10 +1,14 @@
-(require-library "pop3u.ss" "net")
 
-(begin-elaboration-time
- (require-library "invoke.ss"))
+(module pop3 mzscheme
+  (require (lib "unitsig.ss"))
 
-(define-values/invoke-unit/sig mzlib:pop3^
-  mzlib:pop3@ pop3)
+  (require "pop3-sig.ss")
+  (require "pop3-unit.ss")
+
+  (define-values/invoke-unit/sig net:pop3^
+    net:pop3@)
+
+  (provide-signature-elements net:pop3^))
 
 #|
 
diff --git a/collects/net/sendmail.ss b/collects/net/sendmail.ss
new file mode 100644
index 0000000000..0bb3dbb22e
--- /dev/null
+++ b/collects/net/sendmail.ss
@@ -0,0 +1,11 @@
+
+(module sendmail mzscheme
+  (require (lib "unitsig.ss"))
+
+  (require "sendmail-sig.ss")
+  (require "sendmail-unit.ss")
+
+  (define-values/invoke-unit/sig net:sendmail^
+    net:sendmail@)
+
+  (provide-signature-elements net:sendmail^))