[SR-Users] Topoh module & call leg/transaction does not exist

[Olli Attila]

Hello,

I recently started testing topology hiding module on Kamailio and 
encountered a problem where B party hangs up, Kamailio can't identify 
the ongoing transaction to which the BYE should be related to and 
instead of tearing the call down Kamailio just sends back "481 Call 
leg/Transaction does not exist" to B party.
On Kamailio config I have only enabled the topoh.so -module with default 
options and configured this to enable masking:
modparam("topoh", "mask_callid", 1)

Here is what the INVITE to B party looks like and the BYE message coming 
from the B party:
http://pastebin.com/raw/f63zUmid

When debugging on Kamailio end i get:
http://pastebin.com/raw/ZefGAz30

Is this a Kamailio issue or a softphone issue on B party end?

Cheers,

--Olli