We are also looking for an EXACT clone of alibaba.com

It's really EXACTLY the same platform with all their features and the caveats and additional requirements below. We could also consider an already built clone if it meets our additional requirements or could be extended to do so. Project could either be in PHP or ASP.NET.

Must have the IM and CRM features of alibaba.com. If possible, there should be no client to install. Alibaba.com IM requires the installation of a client. I would not mind that but would prefer an "all-web-based" solution. If client is needed, then make it to be very thin.