[Kamailio-Users] Modifying the URI in the header From more than once

[mayamatakeshi]

Hello,
I'm trying to add CallForwarding to my kamailio.cfg.

Before relaying an INVITE from one subscriber to another, I'm required
to modify the From username to the PSTN number of the caller. So I use
uac_replace_from and this works fine.
I can see kamailio sendind this record-route:

Record-Route: <sip:192.168.33.2;lr=on;ftag=qunug47bd1hc74ir26iv;vsf=AAAAAERUW1NLXloEeFVZKRYIDAZKBwRPEQYEH1oLCQAEFS5qcA--;did=b76.5c17ed25>

But then, when the callee fails to answer and failure_route is called,
I need to modify the From username to the PSTN number of the callee
before doing the forward. If I simply try to call uac_replace_from
again inside failure_route, record-route is sent with a duplicate vsf
parameter like this:

Record-Route: <sip:192.168.33.2;lr=on;ftag=qunug47bd1hc74ir26iv;vsf=AAAAAERUW1NLXloEeFVZKRYIDAZKBwRPEQYEH1oLCQAEFS5qcA--;did=b76.5c17ed25;vsf=AAAAAERUW1NLXloEeFVeKRYIDAZKBwRPEQYEH1oLCQAEFS5qcA-->

And this causes two problems:
- the message becomes too big and the GW replies with "513 Message too large"
- the reply is sent back to the caller with duplicate From header and
some UAs do not acknowledge the reply.

So, is it possible to modify the From header more than once?

regards,
takeshi