You may want to have a look at CGI::FormBuilder. It's forms are sticky, and have both serverside and javascript validation.

It's neat.

Update I think that CGI.pm only makes forms "sticky" in as much as they preserve their values each time the form is submitted (ie CGI.pm automatically adds the value="stuff-from-form" when you use it's input method.

Even with this kind of stickyness, a link back to foo.cgi won't post the data to the form that foo.cgi generates, if you want to preserve data like that on the server side, you can look at CGI::Session, which will allow you to associate the contents of the form with an HTTP cookie sent to the browser.