If by "reset the phone" you mean actually pulled the battery out then probably not. This happened to me a while back and pulling the battery fixed it. If you have already tried that, it's probably worth going very carefully back through all message windows and make sure you don't have anything missed and unread. My phone moves text messages to a separate inbox. Go to the home screen and unhide all icons and make sure you don't have a hidden mailbox somewhere.
Occasionally I'll get that red light stating there's a new message, when there isn't. But usually that only happened when I had the bb messenger feature going to my inbox. When I was chatting constantly that red light stayed on.
So I turned off the bb messenger notification in my inbox, and just did the alt+caps+del and reset my phone.
All I can think of is blackberry messenger. The same happened to me until I realized you have to highlight the actual conversation box for the indicator to stop.
Posted from my CrackBerry at wapforums.crackberry.com
