Crash

I was playtesting Kaduria and suddenly it crashed. It's so rare these days that I wanted to report it here. It happened during a call to strlen function:

I think it might have been in the call stack directly, but I don't even need it to find this bug, because strlen is used only six times in the source code and two times in message routines (other four are debug functions) so it in the message class, possibly quite easy to find.