For at least a C++ xAPP using the framework, the attempt to send a heartbeat response is causing a core dump.  It's not known if this is an RMR problem or a problem in the C++ framework.  (If the framework is attempting to use RMR's send message function, rather than return to sender, then it's a framework problem).

In either case, it might be wise to augment RMR to not be vulnerable to xAPP stupidity (sending before rmr_ready shows true).