Do you monitor or pay attention to employees using self installed versions of Instant messanger service (yahoo, AIM, msn).

Some IT managers are concerned that IM can send files that are not virus-checked past corporate firewalls , creating a threat to network security
For example normally AIM runs on port 5190, but the last corporation I worked at had it blocked so I simply made one quick change (edited to port 80) and presto it worked. I was able to receive file transfers and everything. Sophos didnt even think twice about scanning it. Should your company have a policy on policing this? Heads up for sys admins.

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