antz[processing-0142]$ ./processing
Locking assertion failure. Backtrace:
#0 /usr/lib/libxcb-xlib.so.0 [0xb7f7b727]
#1 /usr/lib/libxcb-xlib.so.0(xcb_xlib_unlock+0x31) [0xb7f7b871]
#2 /usr/lib/libX11.so.6(_XReply+0xfd) [0x8c68e55d]
#3 /media/shared/bin/processing-0142/java/lib/i386/xawt/libmawt.so [0x8c760dce]
#4 /media/shared/bin/processing-0142/java/lib/i386/xawt/libmawt.so [0x8c74ad77]
#5 /media/shared/bin/processing-0142/java/lib/i386/xawt/libmawt.so [0x8c74aef3]
#6
/media/shared/bin/processing-0142/java/lib/i386/xawt/libmawt.so(Java_sun_awt_X11GraphicsEnvironment_initDisplay+0x26)
[0x8c74b136]
#7 [0xb1827008]
#8 [0xb1820b6b]
#9 [0xb1820b6b]
#10 [0xb181e236]
#11 /media/shared/bin/processing-0142/java/lib/i386/server/libjvm.so
[0xb769aeac]
#12 /media/shared/bin/processing-0142/java/lib/i386/server/libjvm.so
[0xb786aaa8]
#13 /media/shared/bin/processing-0142/java/lib/i386/server/libjvm.so
[0xb769acdf]
#14
/media/shared/bin/processing-0142/java/lib/i386/server/libjvm.so(JVM_DoPrivileged+0x32d)
[0xb76f87ed]
#15
/media/shared/bin/processing-0142/java/lib/i386/libjava.so(Java_java_security_AccessController_doPrivileged__Ljava_security_PrivilegedAction_2+0x3d)
[0xb73b230d]
#16 [0xb1826898]
#17 [0xb1820a94]
#18 [0xb181e236]
#19 /media/shared/bin/processing-0142/java/lib/i386/server/libjvm.so
[0xb769aeac]
java: xcb_xlib.c:82: xcb_xlib_unlock: Assertion `c->xlib.lock' failed.
./processing: line 17: 1407 Abortito
${APPDIR}/java/bin/java processing.app.Base

That's a problem with Java, not Processing. Replace processing-0142/java
with a new JDK (not JRE) or a symlink to one that works on your machine.
http://processing.org/reference/environment/platforms.html#linux