You must have know Cabir virus if you are using Symbian Series 60 smartphone. If you would like to know more details, you can read this article on MSN.

Summary

• Cabir doesn't work exactly like most computer viruses or worms;
• it's a stand-alone program that must be installed (unwittingly) by each cell phone user.
• Only Bluetooth-enabled phones can be victimized and then only if the phone happens to be one that uses the Symbian Series 60 platform.

If you get infected with Cabir, you've earned it. First you have to be operating in "discoverable" mode, which makes your phone visible to other Bluetooth devices in the area. If an infected phone tries to infect yours, a note will appear asking you to accept a message from a device you may not recognize.

If you do, another dialog box will ask if you really want to install an unverified program. Click "accept" again and you'll get a third dialog box that says, "Install caribe?" One more click and you've got the virus.  

http://slate.msn.com/id/2113909/