please is there any software, which will give website visitor chat interface, and allow support staff to chat via instant messenger with XMPP, ICQ, Google Talk, YM or similar chat protocol?

I used Zopim.com but i listen IMs wont be supported fully.

SmartSupp should work with XMPP which is chat protocol supported by messenger app like Pidgin and more. https://www.smartsupp.com/help/xmpp-windows

Update: here are more softwares for online chat with website visitor: http://internetlifeforum.com/custommer-service/67-best-chat-system-customer-website/