Actually any cell phone that uses the Symbian OS can get several virus's. The Symbian OS powers some cell phone models manufactured by Nokia, Siemens, Sony Ericsson, Motorola and Panasonic.
These virus/worms spread by using text message, Internet downloads, (Ringtones/Screensavers), and Bluetooth which looks for another phone to infect.
http://electronics.howstuffworks.com...hone-virus.htm
That said..the likelyhood of getting a virus is very slim as it's not widespread but it can happen. Only recently (within the last few months) has some of these shown up in the states. So in conclusion if your mobile phone does not use the Symbian OS your safe from any virus because at present this is the only OS thats been exploited.