firefox35 startup crash on mutex - pulseaudio ?

[starr888 at comcast.net]

Greetings & thanks for your work on FireFox on FreeBSD -

I'm getting this crash on FreeBSD 6.4 / KDE 3.5.10
 when starting the browser:

% firefox3
Fatal error 'Recurse on a private mutex.' at line 986 in file /usr/src/lib/libpthread/thread/thr_mutex.c (errno = 2)
Abort trap (core dumped)
%  

another message on the net says this is a pulseaudio problem.

pulseaudio isn't used by anything else on my system.

Is this the only way the firefox35 port can do audio ?

Thanks for your help !