How can I prevent connectivity problems while behind a router?

I am running Yahoo! Messenger 8 on Windows XP. The same issue happened with older versions as well. I maintain agood connection when I am connected directly to my modem. Once I installed my VoIP phone, which included a LinkSys router, I now have issues with Yahoo! frequently disconnecting and reconnecting me. I have tried changing my proxy settings from %26quot;No Proxies%26quot; to %26quot;Firewall with no proxies%26quot; and it has not helped. Does anyone have any other viable suggestions?How can I prevent connectivity problems while behind a router?Yes. To get through firewall do this. Messenger %26gt; Prefferences %26gt; Connection %26gt; Firewall with no proxies %26gt; Apply %26gt; Ok.How can I prevent connectivity problems while behind a router??