Nortel PBX’s are unsupported by Avaya. Business are replacing their Nortel PBX’s with E-MetroTel UCX. UCX has been designed and created by the same engineers that had worked on Nortel PBX. Nortel replacement: You can Migrate your Nortel / Avaya Norstar, BCM, Meridian Option11/51/61 and CS1000 to UCX. UCX provides Nortel PBXs replacement  by supporting the complete Nortel Enterprise portfolio of telephones. And you can forget the complicated product provisioning and licensing. E-MetroTel offers a simple migration for Nortel PBXs to UCX, cost effectively with many new VoIP features and capabilities.