Server :: Debian Becomes Unresponsive While Running Java?

Kernel version: 2.6.26-2-686
Java version: 1.6.0_0

I'm going to run a full system update, but I doubt that'll work.

What happens is I turn the computer on, log in, start the application with:

java -Xmx1024M -Xms1024M -jar minecraft_server.jar nogui

and it will work fine for a while, but then, while we're playing, it'll become unresponsive and crash. I then go over to the physical computer, wake the monitor up by pressing the down arrow, delete the "[[B" that appears, and try to issue the applications stop command to save and close the application. This doesn't work. The computer registers what I type and registers the return, but nothing happens. I switch over to my second console, log in, find the PID of java, and attempt to kill the java process as root. It accepts the command and gives me another line of prompt, but when I switch back to the first console, nothing has happened.

I then switch back and try to issue a shutdown for right now, and it'll get to "Sending processes the SIGTERM signal", and then it waits for them to be killed, but will not progress further than that. I then have to either force the shutdown with the 3-second hold for the power button, or I have to turn off the power bar it's attached to.

Also, if I'm at the prompt and press backspace, which gives me a system beep, it doesn't stop. Instead of one, short beep, I get a never-ending tone, as opposed to the beep.

The computer does run a little hot; It's in a closet and it's kind of crammed, but it's never so hot that you can't handle the computer.