I'm not yet commenting on the security aspects here, but I do think your program would be substantially shorter if you simply used both CGI (for safely decoding the incoming parameters) and CPAN (to manage the fetch, unpack, and build), both of which are included in all modern Perl distributions.

Thanks for the idea though. I'll probably do one myself using those modules and put it in a column, and credit you for inspiration. It's been added to my to-do list.

-- Randal L. Schwartz, Perl hacker