Hi! I have exactly the same problem and i don't know what to do. If i use infopath client, there is no problem. When i try to publish, it also gives an "unexpected error" and "Invalid form template" in the Browser compatibility (verified on server).
I have enterprise features activated in all site collections.
Hope you can help me.
I really needd to publish web-enabled forms in sharepoint, using infopath.
Thanks