Asterisk and SIP out-of-call messages

I’d like to enable SIP SIMPLE messaging. I’ve compiled and installed Asterisk 10.3.0. In sip.conf I’ve set:

accept_outofcall_message = yes outofcall_message_context = messages auth_message_requests = yes

Now I’m trying to connect with Bria for iPhone, with IM enabled. But it says “SMS is disabled for testbeam account”.

Looking in the SIP registration in Wireshark, I see that the server doesn’t include MESSAGE in the Allow header of the registration responses. Presumably this is why Bria says “SMS is disabled”.

Am I missing something?