 
     /**
      *  The result format "e4x" specifies that the value returned is an XML instance, which can be accessed using ECMAScript for XML (E4X) expressions.
+     *  
+     *  @langversion 3.0
+     *  @playerversion Flash 9
+     *  @playerversion AIR 1.1
+     *  @productversion Flex 3
      */
     mx_internal static const RESULT_FORMAT_E4X:String = "e4x";
 
     /**
      *  The result format "flashvars" specifies that the value returned is text containing name=value pairs
      *  separated by ampersands, which is parsed into an ActionScript object.
+     *  
+     *  @langversion 3.0
+     *  @playerversion Flash 9
+     *  @playerversion AIR 1.1
+     *  @productversion Flex 3
      */
     mx_internal static const RESULT_FORMAT_FLASHVARS:String = "flashvars";
 
     /**
      *  The result format "object" specifies that the value returned is XML but is parsed as a tree of ActionScript objects. This is the default.
+     *  
+     *  @langversion 3.0
+     *  @playerversion Flash 9
+     *  @playerversion AIR 1.1
+     *  @productversion Flex 3
      */
     mx_internal static const RESULT_FORMAT_OBJECT:String = "object";
 

     *  The result format "array" is similar to "object" however the value returned is always an Array such
     *  that if the result returned from result format "object" is not an Array already the item will be
     *  added as the first item to a new Array.
     */
    mx_internal static const RESULT_FORMAT_ARRAY:String = "array";

    /**
     *  The result format "text" specifies that the HTTPService result text should be an unprocessed String.
     */
    mx_internal static const RESULT_FORMAT_TEXT:String = "text";

    /**
     *  The result format "xml" specifies that results should be returned as an flash.xml.XMLNode instance pointing to
     *  the first child of the parent flash.xml.XMLDocument.
     */
    mx_internal static const RESULT_FORMAT_XML:String = "xml";

    /**
     *  Indicates that the data being sent by the HTTP service is encoded as application/xml.
     */
    mx_internal static const CONTENT_TYPE_XML:String = "application/xml";
    
    /**
     *  Indicates that the data being sent by the HTTP service is encoded as application/x-www-form-urlencoded.
     */
    mx_internal static const CONTENT_TYPE_FORM:String = "application/x-www-form-urlencoded";

    // Constants for error codes
    /**
     *  Indicates that the useProxy property was set to false but a url was not provided.
     */
    private static const ERROR_URL_REQUIRED:String = "Client.URLRequired";
    
    /**
     *  Indicates that an XML formatted result could not be parsed into an XML instance
     *  or decoded into an Object.
     */
    private static const ERROR_DECODING:String = "Client.CouldNotDecode";
    
    /**
     *  Indicates that an input parameter could not be encoded as XML.
     */
    private static const ERROR_ENCODING:String = "Client.CouldNotEncode";    


     * multiple requests generate a fault.</li>
     * <li><code>last</code> Making a request cancels any existing request.</li>
     * </ul>
     *  
     *  @langversion 3.0
     *  @playerversion Flash 9
     *  @playerversion AIR 1.1
     *  @productversion Flex 3
     */
    public function get concurrency():String
    {
