Default T-Mobile US and MMS?

Prior to my HTC Hero I had a nokia e71-1 and MMS was working fine. I forwarded my gmail to tmomail and picture messages worked fine as well. My T-Mobile plan just has unlimited text, no data. Now however with my Hero I get the MMS message subject but no content and there is a little download button when I click inside the message but nothing happens. I've tried various MMS settings I found on the Internet but none seem to work. Any help is appreciated.