[Serusers] Weird register issue

[Anthony Dean]

Weird issue, only with registers.  Sometimes when I start ser (and openser,
same issue with both)
my test phone (behind nat) will not register allways getting 401
unauthorized back.  But wait a minute
and it will register (without resetting ser or the phone).

Is this a built in feature or a bug (it only happens when I reset
ser/openser after 60 seconds the 
server and phone behave normally).

Got me stumped as the configs on the phone and ser don't change.

REGISTER sip:XX.XX.XX.XX SIP/2.0.
Via: SIP/2.0/UDP 192.168.10.25:5060.
From: <sip:2959770500 at XX.XX.XX.XX;user=phone>;tag=1886287424.
To: <sip:2959770500 at XX.XX.XX.XX;user=phone>.
Call-ID: 147690828 at 192.168.10.25.
CSeq: 1 REGISTER.
Contact: Nathan Gross
<sip:2959770500 at 192.168.10.25:5060;user=phone;transport=udp>;expires=60.
User-Agent: Cisco-CP7905/1.02-040406A.
Allow: ACK, BYE, CANCEL, INVITE, NOTIFY, OPTIONS, REFER, REGISTER.
Content-Length: 0.

SIP/2.0 401 Unauthorized.
Via: SIP/2.0/UDP 192.168.10.25:5060;rport=62686;received=YY.YY.YY.YY.
From: <sip:2959770500 at XX.XX.XX.XX;user=phone>;tag=1886287424.
To:
<sip:2959770500 at XX.XX.XX.XX;user=phone>;tag=264d52ef5b2f408fc315ea210b15c82e
.5681.
Call-ID: 147690828 at 192.168.10.25.
CSeq: 1 REGISTER.
WWW-Authenticate: Digest realm="XX.XX.XX.XX",
nonce="42b9e43447292eaaa08c9b86dcc1e23344ac3c6a", qop="auth".
Content-Length: 0.

Thank You

Anthony Dean
Network Design & Support
Tristar Communications

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