This is just a warning to say that a protection against a crash due to an issue on low memory in an old libssl version has been activated. To increase the shared memory used by kamailio use `-m` parameter, e.g., start wit 256MB of memory: `kamailio -m 256 ...`.
Overall, this is not a bug in kamailio, just a warning about a workaround for a bug in libssl. If you want to discuss more, then send an email to sr-users mailing list.