Broken make distribution on amd64?

For about 2 weeks now I've been seeing failures when trying to spin ISOs
of CURRENT (amd64) and using "make distribution" specifically:

--------------------
pwd_mkdb -L -i -p -d /usr/pcbsd-build90/buildworld/etc  /usr/pcbsd-build90/buildworld/etc/master.passwd
*** Signal 6

Stop in /usr/pcbsd-build90/fbsd-source/9.0/etc.
*** Error code 1

---------------------

It looks like the pwd_mkdb command is core dumping every time:

pwd_mkdb -L -i -p -d /usr/pcbsd-build90/buildworld/etc /usr/pcbsd-build90/buildworld/etc/master.passwd
Abort (core dumped)

Whats odd is that with the same source tree, I'm spinning ISOs of i386 no
problem. I've tried rebuilding the world / pwd_mkdb command with the latest
source a few times, and no luck so far.

Is anybody else seeing this on amd64? Here's the core file:

http://www.pcbsd.org/~kris/pwd_mkdb.core.gz


-- 
Kris Moore
PC-BSD Software