update: found out that this is a call manager issue. the CUCM traces show that the same configured third party sip phone is being returned as the destination for some bizarre reason and hence the user digest authentication actually is incorrect. In CUCM each third party sip device is associated to a ...

Both endpoints can register on their own and we can see the password being correct in the traces. I suppose proof is that they can both register on their own

if Upper & Through is enabled only the first phone shows registered under "registered clients" in brekeke. It also shows registered in call manager (as expected with brekeke's IP Address). as for the packet level for the second phone: Endpoint = E Callmanager = C Brekeke = B Sender :message ...

1. Brekeke Product Name and Version: 3.3.4.4 advanced 2. Java version: 1.7_0.55-b14 3. OS type and the version: 2003 SP1 4. UA (phone), gateway or other hardware/software involved: pbx: CUCM 8.6 endpoint: Media5-fone on iphone 5. Your problem: The first iphone registers OK using upper & through with ...