Unexplained locking failure in Java 6.0_05

I have two Swing GUI programs that display the following locking problem
whenever they are run and however they are run. Two related non-GUI
programs (i.e. all four access the same database via JDBC) don't do this:

Locking assertion failure. Backtrace:
#0 /usr/lib/libxcb-xlib.so.0 [0x7df777]
#1 /usr/lib/libxcb-xlib.so.0(xcb_xlib_unlock+0x31) [0x7df8d1]
#2 /usr/lib/libX11.so.6(_XReply+0xff) [0x51a112f]
#3 /home/java/jdk1.6.0_05/jre/lib/i386/xawt/libmawt.so [0xb56b88ce]
#4 /home/java/jdk1.6.0_05/jre/lib/i386/xawt/libmawt.so [0xb5695067]
#5 /home/java/jdk1.6.0_05/jre/lib/i386/xawt/libmawt.so [0xb5695318]
#6 /home/java/jdk1.6.0_05/jre/lib/i386/xawt/libmawt.so
(Java_sun_awt_X11GraphicsEnvironment_initDisplay+0x2f) [0xb569561f]
#7 [0xb5f41d1d]
#8 [0xb5f3aea5]
#9 [0xb5f3aea5]
#10 [0xb5f38249]
#11 /home/java/jdk1.6.0_05/jre/lib/i386/client/libjvm.so [0x621c40d]
#12 /home/java/jdk1.6.0_05/jre/lib/i386/client/libjvm.so [0x6310378]
#13 /home/java/jdk1.6.0_05/jre/lib/i386/client/libjvm.so [0x621c2a0]
#14 /home/java/jdk1.6.0_05/jre/lib/i386/client/libjvm.so(JVM_DoPrivileged
+0x363) [0x6272153]
#15 /home/java/jdk1.6.0_05/jre/lib/i386/libjava.so
(Java_java_security_AccessController_doPrivileged__Ljava_security_PrivilegedAction_2
+0x3d) [0xb7f5396d]
#16 [0xb5f41d1d]
#17 [0xb5f3ad4d]
#18 [0xb5f38249]
#19 /home/java/jdk1.6.0_05/jre/lib/i386/client/libjvm.so [0x621c40d]

I have not written any assertions into my code, so I'd appreciate any
pointers on where to look for information on what might be causing the
locking assertion to fail and how to get rid of these displays.

Is this a known issue with Java 5.0_05?

TIA
Martin


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |
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