See perldoc lwpcook, which reads in part:

    Lazy people use the HTTP::Request::Common module to set up a suita
+ble
    POST request message (it handles all the escaping issues) and has 
+a
    suitable default for the content_type:

      use HTTP::Request::Common qw(POST);
      use LWP::UserAgent;
      $ua = LWP::UserAgent->new;

      my $req = POST 'http://www.perl.com/cgi-bin/BugGlimpse',
                    [ search => 'www', errors => 0 ];

      print $ua->request($req)->as_string;
[download]

-- Randal L. Schwartz, Perl hacker