Symantec said that it had signed a definitive agreement <A HREF="http://www.eweek.com/article2/0,1759,1907717,00.asp?kc=EWRSS03119TX1K0000594">to buy IMLogic,</A> a maker of security software for instant messaging applications. The acquisition for an undisclosed sum will add IMLogic's IM Manager technology to Symantec's growing stable of messaging security products, and give the company a ready-made solution for the growing number of IM-based worms and viruses.