I saw segmentation violations each time I ran SwingSet2 on
a particular 64-bit Linux machine. Each time, I'd go through
a few (or all) tabs on the Java l&f, and then switch to GTK.
The switch to GTK was slow, and the GUI was sluggish after
that. Then, after a bit of playing with different tabs, I'd
get a SEGV.

I got the SEGV all 3 times I tried running SwingSet2. Here's
a typical error message:

#
# An unexpected error has been detected by HotSpot Virtual Machine:
#
# SIGSEGV (0xb) at pc=0x00000039eca1289d, pid=19695, tid=1088211296
#
# Java VM: Java HotSpot(TM) 64-Bit Server VM (1.6.0-ea-b53 mixed mode)
# Problematic frame:
# C [libgobject-2.0.so.0+0x1289d]

The SEGV happened with both the Swing b53 integration build and the
most recent master build (without Swing's b53 changes).