As of July 20, 2010 users are unable to login to Yahoo Messenger when trying to connect through the Policy Authority for UC Gateway. The error from the Yahoo IM client:
"Messenger encountered a connection problem. Please check the network connection 81003004"
The error message may also read:
"Our system is currently very busy, please try again a little bit later, 81003016"
Yahoo has changed the way their clients connect causing users to not be able to connect when going through Policy Authority for UC.
Install Gateway Product Update 81.83 or later under Gateway Service | Service Configuration | Product Updates.