gistfile1.pl

use strict;
use warnings;

use HTTP::Request::Common;
use LWP::UserAgent;
use YAML;
use JSON::Syck;

my $ua = LWP::UserAgent->new;

my $json = JSON::Syck::Dump({
    userid   => 'asutarute',
    categ_id => '4141873',
});

my $req = POST 'http://channel.pandora.tv/json/v003/playlist.dll/listprg', [ json => $json ];
$req->header( Referer => 'http://channel.pandora.tv/channel/playlist.ptv?ch_userid=asutarute');

my $res = $ua->request($req);

warn Dump(JSON::Syck::Load($res->content));