Pfunk,
The reason why is that the use of Meassaging agents has gone away, in addition the Messaging Agents started using encryption and trying to keep up with these and creating plugins for each of them is a lot of work.
So based on that and over the years we have seen that the use of Yahoo Messenger and the like is VERY low in companies.
More and more fo them do NOT allow them to even be installed.
Good Luck
Ronak
Please marked solved when possible