chan_sip.c: Call from 'ssrleiden' to extension '31715120854' rejected because extension not found

Hi All,

Recently I installed Asterisknow on my HP ML110G5. I run VMware ESXi on it. My Voip provider is speakup from the netherlands.

I set up everything and it has been running like a charm except for one thing. Sometimes it gives the following notice in the full log:

chan_sip.c: Call from ‘ssrleiden’ to extension ‘31715120854’ rejected because extension not found.

When someone tries to call me at 0031715120854 or at 0715120854 I sometimes get this notice and the caller cant connect, they get a message from their own provider stating that the number is not in service (it is not the default english lady from freepbx) The next moment when they try to call, the phone rings.

Problem occurs multiple times a day, but you cant predict when. The log shows nothing and without changing anything you can get a connection at first, but then it just wont connect. I’ve tried it with multiple phones. A Siemens C470IP in combination with a C47 phone, A Linksys SPA-901 and multiple Softphones.

I am probably looking over something, i’m hoping someone over here has got some ideas.

Thanks in advance
Niels Lemmens
The Netherlands

edit
The log lines I see in \asterisk\full when the call wont get through
[Jul 5 19:55:40] VERBOSE[3327] netsock.c: == Using SIP RTP TOS bits 184
[Jul 5 19:55:40] VERBOSE[3327] netsock.c: == Using SIP RTP CoS mark 5
[Jul 5 19:55:40] NOTICE[3327] chan_sip.c: Call from ‘ssrleiden’ to extension ‘31715120854’ rejected because extension not found.