Pre-populate Infopath through code

I have run into a road block while developing a solution in K2.net. It is more of an Infopath problem than a K2.net problem.

I have created a InfoPath document template hosted on a SharePoint Document Library. A webservice will kick off the process. The webservice we contain the user information needed to prepopulate the Infopath template and submit it for work in a user's worklist. I create the process through a C# project but I am unable to manipulate the XML of the Infopath document.

My problem is that I do not know how to populate the InfoPath document with the user information.

Thoughts?

Mike Trouard