merge r25106 to release-1.12

git-svn-id: http://framework.zend.com/svn/framework/standard/branches/release-1.12@25107 44c647ce-9c0f-0410-b52a-842ac1e357ba

library/Zend/Feed/Writer/Extension/ITunes/Feed.php

@@ -205,7 +205,7 @@ class Zend_Feed_Writer_Extension_ITunes_Feed
     /**
      * Set "explicit" flag
      *
-     * @param  bool $value
+     * @param  string $value    Valid values: "yes", "no" or "clean"
      * @return Zend_Feed_Writer_Extension_ITunes_Feed
      */
     public function setItunesExplicit($value)