Snom 821 as a remote extension is not working

[bvfnet]

I have a newly acquired Snom 821 phone running against a 3CX system. The phone has the latest firmware and the 3CX system is version 11 with the latest service pack. The Snom phone is provisioned as a Remote Extension - Out of office with STUN. Long story short the phone seems to provision correctly and it does appear in the admin console under Phones and also has a green dot under Extension Status. There are two other phones on this system and those phones are on the same local network as the 3CX system. From the two local phones I can call the remote Snom phone without a problem. From the remote phone if I attempt to call one of the local phones I get an immediate fast busy signal and the Snom phone displays the word forbidden. I have included below a snippet of the Server Activity log file below. I have read through the published Remote Extension provisioning posts and to the best of my knowledge have everything set as instructed.

In the log below I have replaced the public IP address of our 3CS system with the phrase "3CX-Public-IP". The public IP of the remote phone is replaced with "SNOM-Phone-Public-IP".

Any help is appreciated.

-kg

[code2]
Jan-2013 15:14:52.643 Leg L:22.1[Unknown:] is terminated: Cause: BYE from PBX
22-Jan-2013 15:14:52.593 [CM502001]: Source info: From: "Kevin Gilliatt"<sip:695@3CX-Public-IP:5060>;tag=frkncxnnmx; To: <sip:634@3CX-Public-IP:5060;user=phone>
22-Jan-2013 15:14:52.593 [CM503013]: Call(C:22): Incoming call rejected, caller is unknown; msg=Ivite-IN Recv Req INVITE from SNOM-Phone-Public-IP:5065 tid=-uznecpiagp28 Call-ID=681dff50fada-xs4gix20d2jd:
INVITE sip:634@3CX-Public-IP:5060;user=phone SIP/2.0
Via: SIP/2.0/UDP SNOM-Phone-Public-IP:5065;branch=z9hG4bK-uznecpiagp28;rport=5065
Max-Forwards: 70
Contact: <sip:695@SNOM-Phone-Public-IP:5065>;reg-id=1
To: <sip:634@3CX-Public-IP:5060;user=phone>
From: "Kevin Gilliatt"<sip:695@3CX-Public-IP:5060>;tag=frkncxnnmx
Call-ID: 681dff50fada-xs4gix20d2jd
CSeq: 2 INVITE
Session-Expires: 3600;refresher=uas
Min-SE: 90
Accept: application/sdp
Allow: INVITE, ACK, CANCEL, BYE, REFER, OPTIONS, NOTIFY, SUBSCRIBE, PRACK, MESSAGE, INFO, UPDATE
Content-Type: application/sdp
Proxy-Authorization: Digest username="695",realm="3CXPhoneSystem",nonce="414d535c070fae6c72:4790c0567e48648b5f8d08af8c3b0c89",uri="sip:634@3CX-Public-IP:5060;user=phone",response="83e3e11b83562edec28aa96e61a91dd0",algorithm=MD5
Supported: timer, 100rel, replaces, from-change
User-Agent: snom821/8.7.3.19
Allow-Events: talk, hold, refer, call-info
Content-Length: 317
X-Serialnumber: 000413486C45
P-Key-Flags: resolution="31x13", keys="4"

v=0
o=root 1475543527 1475543527 IN IP4 SNOM-Phone-Public-IP
s=call
c=IN IP4 SNOM-Phone-Public-IP
t=0 0
m=audio 14008 RTP/AVP 0 8 9 18 101
a=rtpmap:0 PCMU/8000
a=rtpmap:8 PCMA/8000
a=rtpmap:9 G722/8000
a=rtpmap:18 G729/8000
a=fmtp:18 annexb=no
a=rtpmap:101 telephone-event/8000
a=fmtp:101 0-15
a=ptime:20
a=sendrecv
22-Jan-2013 15:14:52.426 [CM500002]: Unidentified incoming call. Review INVITE and adjust source identification:
Invite-UNK Recv Req INVITE from SNOM-Phone-Public-IP:5065 tid=-rs53u0n0ekci Call-ID=681dff50fada-xs4gix20d2jd:
INVITE sip:634@3CX-Public-IP:5060;user=phone SIP/2.0
Via: SIP/2.0/UDP SNOM-Phone-Public-IP:5065;branch=z9hG4bK-rs53u0n0ekci;rport=5065
Max-Forwards: 70
Contact: <sip:695@SNOM-Phone-Public-IP:5065>;reg-id=1
To: <sip:634@3CX-Public-IP:5060;user=phone>
From: "Kevin Gilliatt"<sip:695@3CX-Public-IP:5060>;tag=frkncxnnmx
Call-ID: 681dff50fada-xs4gix20d2jd
CSeq: 1 INVITE
Session-Expires: 3600;refresher=uas
Min-SE: 90
Accept: application/sdp
Allow: INVITE, ACK, CANCEL, BYE, REFER, OPTIONS, NOTIFY, SUBSCRIBE, PRACK, MESSAGE, INFO, UPDATE
Content-Type: application/sdp
Supported: timer, 100rel, replaces, from-change
User-Agent: snom821/8.7.3.19
Allow-Events: talk, hold, refer, call-info
Content-Length: 317
X-Serialnumber: 000413486C45
P-Key-Flags: resolution="31x13", keys="4"

v=0
o=root 1475543527 1475543527 IN IP4 SNOM-Phone-Public-IP
s=call
c=IN IP4 SNOM-Phone-Public-IP
t=0 0
m=audio 14008 RTP/AVP 0 8 9 18 101
a=rtpmap:0 PCMU/8000
a=rtpmap:8 PCMA/8000
a=rtpmap:9 G722/8000
a=rtpmap:18 G729/8000
a=fmtp:18 annexb=no
a=rtpmap:101 telephone-event/8000
a=fmtp:101 0-15
a=ptime:20
a=sendrecv
22-Jan-2013 15:14:39.201 Got REGISTER for foreign registrar: registrar host <sip3CX-Public-IP:5060> is not mine!
22-Jan-2013 15:14:10.548 [CM302001]: Authorization system can not identify source of: UnkSrc Recv Req SUBSCRIBE from SNOM-Phone-Public-IP:5065 tid=-wsf7t0opu0fl Call-ID=55000000e93e-10t0e3k3j8dk:
SUBSCRIBE sip:SP0@3CX-Public-IP:5060 SIP/2.0
Via: SIP/2.0/UDP SNOM-Phone-Public-IP:5065;branch=z9hG4bK-wsf7t0opu0fl;rport=5065
Max-Forwards: 70
Contact: <sip:695@SNOM-Phone-Public-IP:5065>;reg-id=1
To: <sip:SP0@3CX-Public-IP:5060>;tag=e904d45e
From: <sip:695@3CX-Public-IP:5060>;tag=ynjbgwks6x
Call-ID: 55000000e93e-10t0e3k3j8dk
CSeq: 9 SUBSCRIBE
Expires: 300
Accept: application/dialog-info+xml
User-Agent: snom821/8.7.3.19
Event: dialog
Content-Length: 0
22-Jan-2013 15:13:40.580 [CM302001]: Authorization system can not identify source of: UnkSrc Recv Req SUBSCRIBE from SNOM-Phone-Public-IP:5065 tid=-h0xvab67566d Call-ID=4f1aff501f2a-hfyu39htk3ls:
SUBSCRIBE sip:999@3CX-Public-IP:5060;user=phone SIP/2.0
Via: SIP/2.0/UDP SNOM-Phone-Public-IP:5065;branch=z9hG4bK-h0xvab67566d;rport=5065
Max-Forwards: 70
Contact: <sip:695@SNOM-Phone-Public-IP:5065>;reg-id=1
To: <sip:999@3CX-Public-IP:5060;user=phone>;tag=4f39b47a
From: <sip:695@3CX-Public-IP:5060>;tag=d3i4hq535g
Call-ID: 4f1aff501f2a-hfyu39htk3ls
CSeq: 9 SUBSCRIBE
Expires: 300
Accept: application/simple-message-summary
User-Agent: snom821/8.7.3.19
Event: message-summary
Content-Length: 0
22-Jan-2013 15:13:38.871 Got REGISTER for foreign registrar: registrar host <sip3CX-Public-IP:5060> is not mine!
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