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All versions of Clarent gatekeeper have allowed you to register a Cisco gateway to teh gatekeeper and it works very well. Gatekeeper 1.2 onwards allows you to use LRQ functionality to connect calls from 3rd party gatekeepers (including Cisco) to clarent gatekeepers as well. I would not really recommend version 2.02 gatekeeper since that is a Unix trial version and I’m not sure it really worked. I’d stick to using NT gatekeeper 1.x, or use teh new C5CM unix product that has H323 functionality. I can give help or advice on setting up Clarent gatekeepers if you contact me on firstname.lastname@example.org.