I have a number of older phones (Aastra 9112i) and a few intercom units (2N Helios IP Verso). I am currently using Televantage as our PBX and looking to move to 3CX. Right now I can only add phones that are in the supported list. Can I somehow just add a "generic" phone in the interface and point the phone to our FQDN with the extensions user/pass? I've tried with the 9112i and we just get "No Service". Activity log doesn't show any connections attempts from our IP. Trying to pick another aastra phone and doing the http provisioning I get "bad encryption cfg" or something similar. Is it possible?