[plt-scheme] develop-servlet not found

The documentation for the web-server states:

   To develop module based servlets, open the module in DrScheme's definitions
   window.  After clicking the Execute button, require the module servlet
   development library.

     (require (lib "develop-servlet.ss"))

But there's no develop-servlet.ss in the mzlib collection.  Perhaps this
should be (require (lib "develop-servlet.ss" "web-server")), but the file
doesn't exist there either.  Am I missing something?  

Version: 203.7-cvs17apr2003 (Unix)

Thanks,
-d