No, this is not a joke. Since my upgrade to Xorg 7.2, I can’t run tomcat from eclipse anymore. It fails with

java: xcb_xlib.c:50: xcb_xlib_unlock: Assertion `c->xlib.lock' failed.

The workaround is simple: start tomcat with

DISPLAY= tomcat5.5/bin/startup.sh

Yes, if you ‘hide’ the graphical interface from tomcat, it works…

WTF is it with Java? (And yes, this is a bug in Java, not in libx11)

Interesting side note: Eclipse still works. And in contrast to tomcat, it actually is supposed to use X11. But it probably always goes through GTK.

P.S. setting LIBXCB_ALLOW_SLOPPY_LOCK=true doesn’t help.