Strange IP address problem in SIP Invite message header

[hforo]

1. Brekeke Product Name and version:
Brekeke SIP Server 2.1.6.6
2. Java version:
V6 Update 7
3. OS type and the version:
Windows Server 2003 R2
4. UA (phone), gateway or other hardware/software involved:

5. Select your network pattern from http://www.brekeke-sip.com/bbs/network/networkpatterns.html :

10

6. Your problem:

The sip invite packet message header is getting an incorrect IP address.

I have pasted the information below:

Message Header
Via: SIP/2.0/UPD 192.168.1.1325;branch=z9hG4bk-d8754z-9036eb6a0d7eb14a-1---d8754z-;rport

Obviously, 192.168.1.1325 is not a valid IP address. Wireshark does show the packet coming in from the (valid) 192.168.1.13

Any thoughts on what might be causing this? The server is returning a 403 forbidden when the client tries to register.

[janP]

who sent such an INVITE packet?
what kind of client is it??

[hforo]

This was from our custom application that uses a 3rd party SIP sdk. I am assuming that this is some sort of firewall/packet inspection issue where the header is actually getting modified but I wanted to rule out any sort of SIP server problem.

[janP]

I think you need to test your custom client in the same local network without firewall. It will avoid such a packet modification problem.