Server CRASH not notifying connected clients

I'm sure someone has ran into this problem before, but I did a search and couldn't find anything useful. Basically say a server (dedicated or not) crashes for some reason (division by zero, or particle engine crash, or any kind of crash, but NOT by typing quit() on the server), then for some reason the connected clients are not made aware of this situation, and they don't disconnect and return to the main menu. It does work correctly if you exit the server normally (quit() for example). That's the behaviour I want, but I think this problem is non-trivial. Basically how do the connected clients know that their server has crashed? Are there any heartbeat like messages sent from server to client every so often? This problem is your standard server-client situation that you encounter in any networked application, but I"m just wondering if there is already a fix for this or methods that I can use. Any help would be greatly appreciated.

thanks