Dave-
Saw your post, i have the same problem, in addition i just e-mailed the
tech-x11 list, while building xfree-4.2.99 with 4.3.1 drivers for
radeon, nvidia, glint etc.. with ..config/cf/Netbsd.cf and
..xc/include/Xthreads.h i get an Xserver with totally screwed up fonts
[On my 164LX].Re-installing.. building with removed
xc/include/Xthreads.h  'fixes' the font problem.  

>I haven't been able to run any Gecko-based browser (mozilla [|-stable],
>galeon, phoenix all tried) since the pthread changes on Alpha.  The
>process 
>doesn't core.  This is what I get in gdb on mozilla-bin and phoenix:

>nbsd_thread_create_inferior: td_open: process callback error

>I've deleted all packages down to and including glib (and pkg_delete -r
>pth), removed ~/.mozilla, and rebuilt many times...  The last time it
>ran 
>without error was with a 1.6J userland and 1.6L kernel.  Gecko browsers
>have failed with the above thread error on 1.6J with 1.6M kernel, and
>now 
>1.6N userland + kernel.

-Mel