7961 регистрация

проблема такая. есть 7961. он за натом и пытается регистрироваться на астериске. результат вот такой

<--- SIP read from UDP:91.200.1.98:49154 --->
REGISTER sip:78.46.118.22 SIP/2.0
Via: SIP/2.0/UDP 192.168.23.120:5060;branch=z9hG4bK16181274
From: <sip:17@78.46.118.22>;tag=0026cb3da21000087c9c3d6b-e8f74d96
To: <sip:17@78.46.118.22>
Call-ID: 0026cb3d-a2100002-9f7baa63-f2bee024@192.168.23.120
Max-Forwards: 70
Date: Mon, 08 May 2006 GMT
CSeq: 104 REGISTER
User-Agent: Cisco-CP7961G/8.0
Contact: <sip:17@192.168.23.120:5060;transport=udp>;+sip.instance="<urn:uuid:00000000-0000-0000-0000-0026cb3da210>";+u.sip!model.ccm.cisco.com="30018"
Content-Length: 0
Expires: 3600

<------------->
[Apr 25 05:19:33] DEBUG[1454]: chan_sip.c:8496 parse_request:  Header  0 [ 33]: REGISTER sip:78.46.118.22 SIP/2.0
[Apr 25 05:19:33] DEBUG[1454]: chan_sip.c:8496 parse_request:  Header  1 [ 59]: Via: SIP/2.0/UDP 192.168.23.120:5060;branch=z9hG4bK16181274
[Apr 25 05:19:33] DEBUG[1454]: chan_sip.c:8496 parse_request:  Header  2 [ 65]: From: <sip:17@78.46.118.22>;tag=0026cb3da21000087c9c3d6b-e8f74d96
[Apr 25 05:19:33] DEBUG[1454]: chan_sip.c:8496 parse_request:  Header  3 [ 25]: To: <sip:17@78.46.118.22>
[Apr 25 05:19:33] DEBUG[1454]: chan_sip.c:8496 parse_request:  Header  4 [ 59]: Call-ID: 0026cb3d-a2100002-9f7baa63-f2bee024@192.168.23.120
[Apr 25 05:19:33] DEBUG[1454]: chan_sip.c:8496 parse_request:  Header  5 [ 16]: Max-Forwards: 70
[Apr 25 05:19:33] DEBUG[1454]: chan_sip.c:8496 parse_request:  Header  6 [ 26]: Date: Mon, 08 May 2006 GMT
[Apr 25 05:19:33] DEBUG[1454]: chan_sip.c:8496 parse_request:  Header  7 [ 18]: CSeq: 104 REGISTER
[Apr 25 05:19:33] DEBUG[1454]: chan_sip.c:8496 parse_request:  Header  8 [ 29]: User-Agent: Cisco-CP7961G/8.0
[Apr 25 05:19:33] DEBUG[1454]: chan_sip.c:8496 parse_request:  Header  9 [150]: Contact: <sip:17@192.168.23.120:5060;transport=udp>;+sip.instance="<urn:uuid:00000000-0000-0000-0000-0026cb3da210>";+u.sip!model.ccm.cisco.com="30018"
[Apr 25 05:19:33] DEBUG[1454]: chan_sip.c:8496 parse_request:  Header 10 [ 17]: Content-Length: 0
[Apr 25 05:19:33] DEBUG[1454]: chan_sip.c:8496 parse_request:  Header 11 [ 13]: Expires: 3600
--- (12 headers 0 lines) ---
[Apr 25 05:19:33] DEBUG[1454]: chan_sip.c:25069 handle_incoming: **** Received REGISTER (2) - Command in SIP REGISTER
[Apr 25 05:19:33] DEBUG[1454]: chan_sip.c:25094 handle_incoming: Ignoring SIP message because of retransmit (REGISTER Seqno 104, ours 104)
[Apr 25 05:19:33] DEBUG[1454]: chan_sip.c:24898 handle_request_register: Initializing initreq for method REGISTER - callid 0026cb3d-a2100002-9f7baa63-f2bee024@192.168.23.120
Sending to 91.200.1.98:5060 (no NAT)

<--- Transmitting (no NAT) to 91.200.1.98:5060 --->
SIP/2.0 401 Unauthorized

тоесть выдает тот же seqno. как это побороть? учитывая что прошивка вроде невлияет. ну или непонятно где ее новее взять. пробывал на

-rw-r--r-- 1 root root 3975754 Апр 24 15:16 cmterm-7941_7961-sip.8-0-3.cop.gz
-rw-r--r-- 1 root root 4108956 Апр 24 15:03 cmterm-7941_7961-sip.8-2-2SR4.zip
-rw-r--r-- 1 root root 4463173 Апр 24 14:10 cmterm-7941_7961-sip.8-3-1.zip
-rw-r--r-- 1 root root 5544946 Апр 24 16:38 cmterm-7970_7971-sip.8-5-3.zip