Windows Messenge Automatically signs off whilst using Wireless

[Guest]

When trying to use Windows Messenger on my laptop via wireless I get signed
out of Windows Messenger automatically (very regularly) making conversations
impossible. I manage to sign in ok but cannot stay in.
When connected directly to the router through my PC I do not have this
problem.
I am using a Linksys WRT54GX wireless router and ntl broadband, with windows
messenger 5.1 on XP.
Is this a firewall issue?

 

[Guest]

I have the same problem with regard to being signed out a lot. In addition,
i often do not receive messages that are sent to me when i have a
conversation window open, and the person sending the message does not receive
the usual error message that you get when a message cannot be delivered.

I am using a d-link DI-624 wireless router and MSN messenger 7.5 on XP