Got a IPEdge with the MP114/4S/SIP gateway for the fax machine and a Polycom , I am unable to do a conference call from any of the ports on the FXS gateway.

Not positive, but I dont think it is possible. Its a SIP extension and I dont think the CiX or the IPEdge allows sip extensions to complete a conference call. With an IP polycom, you would need to register it as two extensions and have the polycom do the conference.