Anti-virus firm F-Secure Corp. has discovered another variant of the Commwarrior worm, which 
attacks phones that use the Symbian Ltd. operating system.
Commwarrior.Q can be spread via text messages, Bluetooth connections, or swapping memory cards in your phone, according to Tony Magallanez, systems engineer for F-Secure. The mobile malware launches its own browser page after it infects the device, but can be disabled by the user or blocked by mobile anti-virus software, Magallanez says.
As with many current mobile viruses, this piece of malware’s current potential for mayhem doesn’t seem that great. "It seems to be a fairly low infection rate… probably no more than a few hundred users," says the engineer. Unstrung - More Mobile Malware - Wireless Networking News Analysis