Hi Brett,
Could be any number of things from cross domain security (is the new server in the same domain as the user opening the form? does making the form full trust solve the issue?) to host header issues resulting from the SP2 reinstall.
You've been using ADWS for several years. We have a more recent version if you're interested in that, send me an email. I don't think it has anything to do with a bug in ADWS, but it would be good to have you on the most recent version anyway (more features, etc.).
If you want to purchase 1 support incident, I can also have an engineer call you and debug the issue over live meeting.
Otherwise, please investigate whether making your form full trust makes the problem go away. If so, it's likely a domain trust issue. That's my guess. If that doesn't work, we need to check the SharePoint install.
Best regards,