Hi,Do you have Polycom UC Software Version # 3.1.2 or higher?http://www.polycom.com/products/voice/interoperability/platform_compatibility_vvx.htmlAlso try to select Standard SIP Profile and make sure to use client configuration with DN as Username a...

I checked the config.Can you elaborate a bit more on how the users are supposed to dial out?Do they dial out through a Nortel PBX?Again ... What is the exact call flow?

Hi Dave,In this case it's interesting to see the topology and the call flow.Please include this.Thanks,Charley