Hey nickybrg,
yes they are both registered, and even after getting the unaviliable prompt, they still remain avaliable. The prompt comes form the X-Lite softphones we're using ion our lab setup, newest version.
Here's the log gfrom when i try to dial ext 10,000 which is the external voip line that is registered from extension 1000....kerep an eye on the 1000 vs 1000 they look so similar in the log!!
10:08:07.088 CallConf:

nIncoming [CM003002] Call(20): Destination not available for call from sip:
[email protected]:5060 to sip:
[email protected]:5060
10:08:07.088 StratInOut::initialize [CM004003] Call(20): Can't call external line DN
10:08:07.010 CallConf:

nIncoming [CM103002] Call(20): Incoming call from 1000 (Ext.1000) to sip:
[email protected]:5060
08:42:45.603 ServRegs:

nAdd [CM113002] Registered: Ext.1003
08:42:45.416 ServRegs:

nRemove [CM113003] Unregistered: Ext.1003
08:22:45.197 ServRegs:

nAdd [CM113002] Registered: Ext.1003
08:22:44.994 ServRegs:

nRemove [CM113003] Unregistered: Ext.1003
07:57:18.885 ServRegs:

nAdd [CM113002] Registered: Ext.1003
07:35:48.338 ServRegs:

nAdd [CM113002] Registered: Ext.1000
07:35:47.916 ServRegs:

nAdd [CM113002] Registered: Ext.1000
07:34:00.244 CallConf:

nIncoming [CM003002] Call(19): Destination not available for call from sip:
[email protected]:5060 to sip:
[email protected]:5060
07:34:00.244 StratInOut::initialize [CM004003] Call(19): Can't call external line DN
07:34:00.150 CallConf:

nIncoming [CM103002] Call(19): Incoming call from 1000 (Ext.1000) to sip:
[email protected]:5060
07:33:54.525 ServRegs:

nAdd [CM113002] Registered: Ext.1000
07:33:54.197 ServRegs:

nRemove [CM113003] Unregistered: Ext.1000
07:33:53.916 ServRegs:

nAdd [CM113002] Registered: Ext.1000
07:13:21.025 ClientRegs:

nSuccess [CM113005] Registration of sip:
[email protected] is successful
07:13:20.244 ExtLine::Register [CM110004] Send registration for <sip:
[email protected]>
07:13:20.244 ExtLine::Register [CM110001] Use External IP for device line registration DN='10000' device='Other 3CX'
07:13:19.947 StunClient:

rocess [CM115002] STUN resolved external IP=74.59.101.176:5060 by server 80.239.235.209
07:13:19.822 StunClient:

rocess [CM115001] Send initial STUN request to 80.239.235.209
06:53:20.431 ClientRegs:

nSuccess [CM113005] Registration of sip:
[email protected] is successful
06:53:20.010 ExtLine::Register [CM110004] Send registration for <sip:
[email protected]>
06:53:20.010 ExtLine::Register [CM110001] Use External IP for device line registration DN='10000' device='Other 3CX'