To solve the problem, run the following to restart Bonjour service
sudo launchctl unload /System/Library/LaunchDaemons/com.apple.mDNSResponder.plist
then
sudo launchctl load /System/Library/LaunchDaemons/com.apple.mDNSResponder.plist
updated:
Since this solution is not that practical, I ended up using Adium to online gTalk on Mac.