Format Date from XML

I’m trying to read and format a date from XML

The XML date is :

<pubDate>Thu, 28 Aug 2008 09:19:45 -0500</pubDate>

I have the following code:

		var newsDate:Date = new Date ();
		newsDate = xml.item[0].pubDate as Date;

Which returns null.

I need to get this input into a form that Date can recogize so that the date can be formatted as MM/DD/YY.

This is in Flash, not Flex, so mx.formatters.DateFormatter is not an option.

Any suggestions?