We have some troubles with our Instant Messaging, which is just everything but instant...

In fact, some of our users complain about messages that are send, but which appear on the contact's screen only minutes later (sometimes not at all). The problem is that it is not always the case, sometimes it just works as it should, and other times it is impossible to trust the system.

There are other issues with people beoing available on their session but seen as disconnected for the others who can't discuss with them whereas this worked the day before or even 10 minutes before.

Are there any other cases reported, any solution ? If any information is needed to find a solution, please ask !

Thanks in advance for your help.