This samples demonstrates how to promote and demote values inside an Xml message into the message context and back into the message again.
This sample will work with BizTalk 2004 and BizTalk 2006.
Get more information from the original blog post on this topic: http://www.biztalkgurus.com/blogs/biztalk/archive/2004/10/07/Property-Promotion-and-Demotion-in-BizTalk.aspx