I've run into this a few times on squeeze to wheezy upgrades, and once on a fresh wheezy install.
I haven't been able to track down the source of it, but I have a work-around -- if you change the shell of the dirmngr user in /etc/passwd to be /bin/bash instead of /bin/sh, the start-up script works. You may have to also do "nscd -i passwd" to invalidate the name-service cache of the old entry. -- A. -- Andrew Reid / andrew.ce.r...@gmail.com