At a guess, you have a syntax error because you are missing ); at the end of your open command.

Note that you should learn how to find the error logs to get your debugging messages. This helps a lot in tracking down errors. Also note that it is unwise to do an open without adding an error check. Like this:

open(MAIL, "| sendmail $recip") or die "Cannot mail $recip: $!";
[download]

(Add usual lectures about strict.pm, to use CGI rather than cgi-lib which it looks like you're using, etc.)