cisco sx20 register sip server kamailio 4.1.3 fail

[tdaniel0417]

I have one cisco sx20 but fail to registery to sip server kamailio in linux

here is my sx20 sip config 

default transport:TCP

displayname:  901@mydomain.com

tlsverify: off

outbound:off

type:standard

uri: sip:901@mydomain.com

authentication1: 

   login:901

   password:xxx

proxy1

   address: 10.10.10.1

   discovery: Manual

but get status:

Failed: 401 Unauthorized

also , I got sip trace in kaimailio:

REGISTER sip:mydomain.com SIP/2.0
Via: SIP/2.0/TCP 10.10.10.2:5060;branch=z9hG4bK0c3937277165dc026c5547d0ec18d643.1;rport
Call-ID: 591bb245c524f8ac4fbc34be9ac14723
CSeq: 21066 REGISTER
Contact: <sip:901@10.10.10.2:5060;transport=tcp>;+sip.instance="<urn:uuid:85f83850-c321-5a5f-ad1c-65861e03d5cc>"
From: <sip:901@mydomain.com>;tag=8a480fc854666538
To: <sip:901@mydomain.com>
Max-Forwards: 69
Route: <sip:10.10.10.1;lr>
Allow: INVITE,ACK,CANCEL,BYE,UPDATE,INFO,OPTIONS,REFER,NOTIFY
User-Agent: TANDBERG/518 (TC6.3.0.3d8e7d1)
Expires: 3600
Authorization: Digest nonce="U4AKGVOACO2ACgcvysTBL71K38QAnQ4WeOFqw4A=", realm="mydomain.com", username="", uri="sip:mydomain.com", response="07dbdec7fe7fc04a25b42c767c6fdde2", algorithm=MD5
Supported: replaces,100rel,timer,gruu,path,outbound
Content-Length: 0

I see digest have username="", but i am not sure whether it is normal.  

any idea to fix ?

[jinhyuk lee]

Hi 

I have a same problem.  

The SIP server is Brekeke.

TC 6.1.1 version  didn't have a problem, I saw username in username field .

But I didn't see username in username field over TC 6.3 

TC 7.x has a same problem..... 

Actually i don't know, it's a bug or the other logic in TC software....

Does who explain for this symptom....