I just checked in a fix to sys/arch/alpha/alpha/machdep.c for a
problem which was causing a bunch of lossage for native thread
programs. Essentially, there was a chance that a thread blocked in a
system call would not have its floating-point state restored and would
inherit the state of the previous thread to run on that LWP.

The most obvious symptom (to me) was that mp3 decoding in xmms was
slightly "chirpy", but since gcc's alpha target likes to use FP for
lots of other things, it probably caused many other problems. Mozilla
seems better to me, but it's somewhat flaky in general, so I don't
think *all* of the mozilla-thread problems are fixed.

Give 'em another try.

        - Nathan