relative_to_absolute

  <?php
  
  function relative_to_absolute ($text) {
    
    $lang = language_default();

    global $base_path;
    $text = preg_replace(
      '/(src|href)=(\'|")' . preg_quote($base_path, '/') . '/',
      '$1=$2'. url('<front>', array('absolute' => TRUE, 'language' => $lang)),
      $text
    );

    return $text;
  }