We've got a core file after disabling apport, and here is the backtrace. Please let us know if anything else is needed.
(gdb) bt full #0 0x00007f7b07791ab5 in perl_reload () from /lib/x86_64-linux-gnu/kamailio/modules/app_perl.so No symbol table info available. #1 0x00007f7b07793e7f in app_perl_reset_interpreter () from /lib/x86_64-linux-gnu/kamailio/modules/app_perl.so No symbol table info available. #2 0x00007f7b0778e2b1 in perl_exec2 () from /lib/x86_64-linux-gnu/kamailio/modules/app_perl.so No symbol table info available. #3 0x00007f7b0778e26e in perl_exec1 () from /lib/x86_64-linux-gnu/kamailio/modules/app_perl.so No symbol table info available. #4 0x000056222b5e3b2f in do_action () No symbol table info available. #5 0x000056222b5f2a97 in run_actions () No symbol table info available. #6 0x000056222b5f331a in run_top_route () No symbol table info available. #7 0x000056222b7a931f in receive_msg () No symbol table info available. #8 0x000056222b65886a in udp_rcv_loop () No symbol table info available. #9 0x000056222b54fccc in main_loop () No symbol table info available. #10 0x000056222b55ce41 in main () No symbol table info available.