# send password:
    $ENV{"PATH"} = "";
    open (MAIL, "| /usr/lib/sendmail $email"); 

http://www.perl.org/troubleshooting_CGI.html
--------------------------------------------------------

Is the script complaining about insecure dependencies? 

If your script complains about insecure dependencies, you
are probably using the -T switch to turn on taint mode.

Any data originating from outside of the program (i.e. the enviroment) is considered tainted.

Environment variables such as PATH and LD_LIBRARY_PATH are particularly troublesome.

You have to set these to a safe value or unset them completely, as I recommend.

You should be using absolute paths anyway.

If taint checking complains about something else, make sure that you have untainted the data.

See the perlsec man page for details. 

-ans