SIGSEGV on exit

On exit minecraft prints out an error (in terminal) of SIGSEGV. This generates a *.log file with more information. These log files pile up each time I play, so it'd be nice if it didn't crash.

What I expect:
Minecraft exits gracefully

What does happen:

$ java -jar ~/Games/Minecraft/minecraft.jar 
27 achievements
208 recipes
Setting user: <removed>
LWJGL Version: 2.4.2

Starting up SoundSystem...
Initializing LWJGL OpenAL
    (The LWJGL binding of OpenAL.  For more information, see https://www.lwjgl.org/)
OpenAL initialized.

Stopping!

SoundSystem shutting down...
    Author: Paul Lamb, www.paulscode.com

#
# A fatal error has been detected by the Java Runtime Environment:
#
#  SIGSEGV (0xb) at pc=0x00007fb29789ec58, pid=20185, tid=140405235873536
#
# JRE version: 6.0_24-b24
# Java VM: OpenJDK 64-Bit Server VM (20.0-b12 mixed mode linux-amd64 compressed oops)
# Derivative: IcedTea6 1.11.4
# Distribution: Ubuntu 12.04 LTS, package 6b24-1.11.4-1ubuntu0.12.04.1
# Problematic frame:
# C  [libX11.so.6+0x33c58]  XQueryExtension+0x28
#
# An error report file with more information is saved as:
# /home/steven/.minecraft/hs_err_pid20185.log
#
# If you would like to submit a bug report, please include
# instructions how to reproduce the bug and visit:
#   https://bugs.launchpad.net/ubuntu/+source/openjdk-6/
#
Aborted (core dumped)

Steps to reproduce:

1. Start minecraft via terminal.
   java -jar path/to/minecraft.jar

2. Login

3. Exit minecraft (Exit button or top X button)

4. Observe crash text and new *.log file