Problem with web service

Hi everybody. I'm new to K2.net and I have a little problem. I use new version of K2.net with SP3. When I want use Web Service I get error like this:

"Version 2.0 is not a compatible version."

In recent version of k2.net it worked fine. I have k2.net installed on machine with framework 1.1 and 2.0. Anybody know what I need to do, to make it work?