Attacks against public instant messaging networks soared over 800 percent in December 2005, compared to the same month last year, a security company announced Tuesday. The year’s last month saw 241 new threats, said IMlogic, down from the 307 in November and the 294 in October. “The growth in the level of sophistication and the advanced nature of the malware payloads such as rootkits and information gathering agents sends a signal to IM users that IM security is no longer a ‘nice to have’ technology,” Sakoda said in a statement.