Just for the record, [56f1243](https://github.com/kamailio/kamailio/commit/56f12436c2637a0811da9cc55f48a18e...) caused a crash because of a double free. Was reverted with pull request #1839
Hmm, maybe that is different on master. I've been running that on 5.1 for over a year. I'll have a look.