How can I get the XML as text from a DOM object?

How can I get the XML as text from a DOM object?

I'm trying to make a few SOAP calls using jQuery. What I'd like to be able to do is read the results of my first SOAP call in as XML, convert that to a jQuery DOM object, make modifications using jQuery selectors, and then output the DOM object as XML text and submit it back to the SOAP receiver.
 
So far I've managed to get my SOAP response read in via the $.xmlDOM plugin. My next question is: how can I convert the DOM object this plugin creates to XML easily (and by easily I mean: without running an on-the-fly parser or similar structure over it to extract all the tags etc.)?
 
I've tried using the .xml property to get this, but the DOM object generated by the $.xmlDOM call doesn't have said property. Is there an easy way to convert jQuery DOM objects back and forth between text and object representation?