OpenSuSe 11.3 slow connection

Recently, i have issues with connection to the internet using openSuSe 11.3. Connection are difficult to established to the server and very slow. Even pinging will take some time to resolve name to IP. What happened is in /etc/resolve.conf there is nameserver that inactive anymore, so it try to connect to unavailable nameserver. What i have is just put comment mark # to disable the unavailable nameserver.