This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
XPath has some functions that you can use to "ignore" the namspace if you're certain they're correct. Other than that you could start ripping apart the XML and resolve the namespace prefixes yourself. By the way, what do you mean by "resolve the namespace"?