Depending on how your "target" is implemented, it is a bad idea to mix GET and POST parameters. Personally, I wouldn't use LWP::UserAgent anymore for web automation but WWW::Mechanize, which shields you from those mundane tasks of figuring out the values and names (No, personally, I use my own module, WWW::Mechanize::Shell, but that's just a frontend to WWW::Mechanize).

I tried a plain GET url in my browser and that dosen't work, so for further diagnosis, please also post the original url (the one giving you the form you're trying to fill out).

perl -MHTTP::Daemon -MHTTP::Response -MLWP::Simple -e ' ;    # The  
$d = new HTTP::Daemon and fork and getprint $d->url and exit;#spider
($c = $d->accept())->get_request(); $c->send_response( new   #in the
HTTP::Response(200,$_,$_,qq(Just another Perl hacker\n))); ' #  web
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