In what way does it "not work"? Are there any error messages in any logs? That is where any output on STDERR would end up in. Do you get a 500 server error? If not, what do you see? Have you looked into the HTML source to check exactly what the script produces? Have you checked the values of $? (child process error) and $! (OS function error) to see if GPG tried to signal an error to its caller?

I'm sure there's a few more places to look which I forget in this off the top of my head listing, but that should suffice to begin with. :-)

Finally, you might want to add use CGI::Carp qw(fatalsToBrowser warningsToBrowsers); during development. (But remove the fatalsToBrowser warningsToBrowsers parameters once the script is publically accessible - it is none of your visitors' business why your script broke, if it did.) See Ovid's CGI course for a good beginner's resource on CGI programming.

Makeshifts last the longest.