We're having an issue similar to
ZBX-10291. One of the different I see if that the action record the escalations event is point too is actually in the actions table.
Basically the server crashes whenever it send's an alert email. It was sending email fine last week then I stopped it because I had it reporting on all events. I changed it to only send on Diaster events and the first pass it ran crashed the server.
I'm going to test sending for other severity level's to see if mail will send.
I've attached logs, screenshot of database, and what I think you're looking for on binary's (If not please let me know where the best place to look would be, I just did an rpm install.)