Are you using FormMail?
I believe this is a specific tag to form mail, and not to "CGI".
CGI stands for Common Gateway Interface and can be written in a variety of languages. If you were to put that tag into any form it would do nothing unless the script that acts on the form thinks that it means something.
All I can find on that specific tag is FormMail.
If you indeed are using formmail it would be much more helpful to include that next time

Otherwise crouse is 100% correct and you would have to edit the script to check for all fields, and respond appropriately.
Jkrohn