Nortel Networks and Microsoft Corp. clarified their joint unified communications endeavour at a customer event in New York last month. The companies described three new systems: UC Integrated Branch, an appliance for VoIP and unified communications at branch-sized offices, expected for the fourth quarter of 2007; a unified messaging platform combining Nortel’s enterprise IP-PBX and Microsoft’s Exchange Server for email, expected for the second quarter, and; a conferencing system marrying Nortel’s conferencing back end to Microsoft’s unified communications client, expected for the fourth quarter.