And remember Life is short so use WWW::Mechanize; It will automatically work with cookies for you, process forms, links etc.

use WWW::Mechanize;

my $mech = WWW::Mechanize->new();
$mech->agent_alias("Windows IE 6");

$mech->get($base);
$mech->submit_form(
    with_fields => {
        login => $user,
        password => $pass,
        'btn_login.x' => 66,
        'btn_login.y' => 17,
    },
);
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