The e-mail app that came on my T-Mobile T989 was just lame. For one thing, each message had to be deleted twice, once form the inbox, once from the deleted items folder, and each deletion took 3 or four taps. If you get 50 or so messages a day, as I di, it's a real time-waster.
I've found K-9 mail to be reliable and easy to use.
-WillieB