[PLUG] Messenger throught proxy

[Shodhan Bhave]

I have a fedora 6 system connected to tata indicom broadband
connection.I have another laptop running windows xp which is connected
through a realtek card to the base system.
I run squid proxy, and firefox and IE are running fine on the laptop.
But i could not connect yahoo messnger and msn live through the proxy.I
have configure the messenger to use the proxy but I could not find any
options to use proxy on msn live or mirc as well. Can someone pl guide
me?
Shodhan