3rd party sip phone or non nec sip phone - 8100/9100

[cayres1003]

I have had a lot of success connecting other sip phones to the 8100 and 9100. But I have run into 2 different locations having the same problem with one of their sip phones. If you call the phone it says "sip out of range" and you can't establish a call. I don't know if this related to the pbx or the phone itself. The phone can call out. On another note, not sure if this related yet or not, they are both customers that are right at their limit with either ports or ip phone licenses. This might be a contributing factor.
If any of you guys have seen this, please comment.

 

[Ragnorak]

Varies by manufacturer, for example Snom experiences this exact behavior connected to an NEC system if you don't check "enable broken registrar." NEC's SIP implementation isn't in perfect compliance with the RFC so you may need to enable or disable options to make the particular SIP endpoint more forgiving or it might simply be incompatible.