elegant php array combinations algorithm

<?

//by Shimon Dookin

function get_combinations(&$lists,&$result,$stack=array(),$pos=0)
{
 $list=$lists[$pos];
 if(is_array($list))
  foreach($list as $word)
  {
   array_push($stack,$word);
   if(count($lists)==count($stack))
    $result[]=$stack;
   else
    get_combinations($lists,$result,$stack,$pos+1);
   array_pop($stack);
  }
}

$wordlists= array( array("shimon","doodkin") , array("php programmer","sql programmer","mql metatrader programmer") );

get_combinations($wordlists,$combinations);

echo '<xmp>';
print_r($combinations);

?>