Update the application to fix it's connectivity to the infrastructure. Dunno about any of you but I noticed it's always flaky and sometimes (probably due to low coverage or connectivity issues) it will send messages but not receive them. Yet when you go to Windows Live Messenger on your computer it'll show the messages your BlackBerry failed to receive while running the application.
This is ultimately frustrating as WLM doesn't work out of the box. I keep having to sign in a few times to get a no-issues session. IM+ Pro and other unofficial MSN applications doesn't seem to have these problems even in poor coverage so it's safe to say it's the application.
But unless this issue trends it would be something they'll notice and pass on,
you should go on the developer forum, or in the beta zone, and you should review the app in Appworld with the issues
I think WLM is low on RIM's priority list. They wouldn't give a hoot about small matters like this. I wish someone will prove me wrong, but RIM isn't a company which excels in consumer relationship.
There's a reason why I don't use any native IM apps on the BlackBerry. I shrink them out of every OS install, and I only use Trillian. Good stuff, more features as well.
My only gripes about this app are that it's often necessary to hit menu followed by refresh (yahoo and google talk don't even have the refresh option because it's not necessary on those apps) and the inability to send im's to offline contacts. On both yahoo and googletalk (RIM's versions) and on the aol version of aim it's possible to send im's to offline b�ddies.