Unwanted slash in a form

Yo All,
here is the question:
Forward: the server runs a debian3 with apache/php/mysql. Both WP1.2. and 1.5 work fine for the normal activities.

The problem
I made a form to handle subscription to a civil rights NGO, using FormMail.pl script.
https://www.alcei.org/?page_id=9
The script runs smoothly in a static site (the one I’m porting the NGO site from).

When I fill in the fields and press the “send” button the script tells me that there is something wrong. I then compared the post source to post-as-displayed and I discovered that during the page processing a “/” is added close to mail address making it working not properly.

I then went back to post, deleted all of the unwanted slahses, saved the post, but I got the same problem again…

Any idea to help me?

Thanks a lot