/**
  * Returns a formatted description field, depending on descriptionHtmlSyndicated and
  * $descriptionTruncSize properties
  * @return    string    the formatted description
  */
 function getDescription()
 {
     if (isset($this->encoding)) {
         $enc = $this->encoding;
     } else {
         $enc = 'ISO-8859-1';
     }
     $descriptionField = new FeedHtmlField($this->description, $enc);
     $descriptionField->syndicateHtml = $this->descriptionHtmlSyndicated;
     $descriptionField->truncSize = $this->descriptionTruncSize;
     return $descriptionField->output();
 }

$rss->syndicationURL = "http://www.dailyphp.net/".$_SERVER["PHP_SELF"]; 
$image = new FeedImage(); 
$image->title = "dailyphp.net logo"; 
$image->url = "http://www.dailyphp.net/images/logo.gif"; 
$image->link = "http://www.dailyphp.net"; 
$image->description = "Feed provided by dailyphp.net. Click to visit."; 
//optional
$image->descriptionTruncSize = 500;