What you describe (infection via Bluetooth and then sending of MMS messages) is typical for the viruses of the CommWarrior family. But only on the surface. They send themselves via MMS - not via SMS. They use the numbers in your phone book - not unknown numbers. Maybe you have something new.

If it's a CommWarrior virus, then the most widespread variants are A, B, C and Q. If you have any of the first three, the following free utility will get rid of them. Removing the Q variant is trickier!!!

Global Mobile