Out of nowhere today, I've started getting txt messages from 9016 that look like this:
go to the market and get the SPC app and add 9016 to the blocked numbers and you wont see it again
While that would probably work it won't fix the issue, it just hides it from you.
There are a couple of things that can cause this. Any sort of third party messaging app can cause weird issues like this or if something becomes corrupted for some reason. The messages are normally intercepted by the voicemail app before they get to the messaging app, but if something is not working correctly the voicemail app can miss the message, so it will instead appear in messaging.
1. Open the Sprint Voicemail application
2. Press Menu and choose Compose
3. Record a message that is ~2-3 seconds long, it can be longer but doesn't need to be.
4. Send it to firstname.lastname@example.org
5. Within ~15 minutes your phone will re-register with the Visual Voicemail server and the messages should stop appearing.
That should fix the issue most of the time. This method is similar across all Android visual voicemail phones, and even the Samsung Instinct devices. Blackberries and iPhones have a completely different method.