This is one of few things that's also been really bugging me with my Droid2. That is, outgoing messages will fail to be delivered and get stuck in the Outbox, only option is to delete, etc. Refreshing the outbox seems to have exactly zero effect.
However, I toggled Data-Push off/on and sent a test message. I don't know if messing with Data-Push had anything to do with it, but the result was first
two messages in the outbox (the original stuck message plus the test message), then within a minute, both messages were sent and life was good.
Lastly, please forgive me a bit of editorializing...
"Sent" messages should just keep automatically retrying until sent.
Period. This includes email, SMS and MMS. Users should not have to jump through hoops to resend. It should "just work." I understand there can be cell coverage problems or whatever, and feel free to alert me that there's a delay, but otherwise, I've already expressed my desire to send the message -- so send the damn message!
Thanks, I feel better now.
-cw-