Congratulations! You've been nailed by a "home page hijacker".
Ad Aware products mentioned above should take care of it. If not got to
http://www.safer-networking.org/inde...=en&page=about
and download the free copy of spybot search and destroy (Spybot S&D).
You might find more info on
www.datadoctors.com which host a Saturday radio show here in Phoenix, AZ. They've discussed this problem several times and have some posts on their website for solutions - mostly free help with general computer problems, not necessarily pocketPC targeted data.
Good luck...