The problem is that source address family is different than target address family, and HEP seems to have only one field for address family:
- https://github.com/kamailio/kamailio/blob/master/src/modules/siptrace/siptra... - https://github.com/kamailio/kamailio/blob/master/src/modules/siptrace/siptra...
So apparently you need to extend HEP and Homer Sipcature server, not only siptrace.
I am closing it as it looks not something easily to deal with, it is not only about Kamailio. If I am wrong, you can reopen, or just make a pull request with the changes.