Can any Avaya experts out there tell me if the SIP-based Avaya IP Office 9600 phone can be used in a 3rd party SIP environment? I've had a chat with one of their online sales reps who says that "to the best of his knowledge" they will not work and Avaya won't support it. He suggested that I contact my local Avaya dealer for a more definitive answer. I think it's probably technically possible (though I've never touched one so I don't know that for sure) but I'm wondering if Avaya supports it (ie can I purchase a support contract so I can open a ticket on an issue). Any insight would be appreciated. Thanks -Adam