XMPP Client Implementation like Spark IM for .NET developers

We can use Spark IM for extensive client support like as help desk, agent services, duplex messaging service, group discussion, conferencing, a full-fledge instant messenger or as call center application. But Spark IM is a Java based implementation, so If you guyz need an open source for solid and extensive implementation of XMPP client version like Spark IM, based on C#.Net, ping me at -- a.rahmanbd@yahoo.com