hey..definitely go for IM Manager by IMlogic, I use this software, and its really perfect. It secures IM conversation, allow you to log all conversations on your network, you can block whatever you want, its really good and very affordable. They call it version 7 because its really easy to use and can be set up in just 7 mouse clicks. If you have any questions about it, please dont hesitate to ask. Regards
IMsecure is actually a good program but IM Manager combines IM Management + the job of IM secure. It secures IM's..it is a partner with Symantec so it runs symantec av scan on file transfers, and it allows you to manage ALL IM's on your network.