Hi,

Call to a number forwarded to a FAX by using two Kamailio proxies. 

(INVITE) --> KamailioA --> GW1 --> KamailioB --> GW2 --> FAX
FAX --> (RE-INVITE) --> GW2 --> KamailioB --> (TO Header being corrupted)

KamailioB is corrupting TO header when receiving RE-INVITE and causing the call to fail.

1) Only one "uac_replace_from()" is being used in each Kamailio.
2) GW1 is adding +1 (using E164 format) to URI and FROM headers.

I was wondering if any of the above might cause the TO header corruption.

Any help would be appreciated.
AL