Nortel JTAPI Provider / Peer class

Question

I'm just getting started with the Java Telecommunications API (JTAPI) and have gotten stuck on the inital connection to the PBX with the API. Is the jtapi Peer implementation class for Nortel equipment available for free somewhere, or do I need to purchase it from Nortel? This is the class that would be used in the code shown below to replace "java.path.to.JtapiPeerImplementation":
JtapiPeer peer = JtapiPeerFactory.getJtapiPeer("java.path.to.JtapiPeerImplementation");