Antivirus researchers are investigating <A HREF="http://news.zdnet.com/2100-1009_22-5602919.html?tag=zdnn.alert">a new Trojan horse</A> that could prove to be a more pervasive threat to cell phones than Cabir. The malicious software, dubbed "CommWarrior" and described as a virus by some antivirus companies, takes aim at the version of the Symbian operating system running on Nokia Series 60 handsets. CommWarrior attempts to spread by sending messages via Bluetooth wireless connections and Multimedia Message Service--different from the Cabir virus, which only used Bluetooth to proliferate.