It's now fixed with the newer versions of mdadm. I think this was more a config problem than a software problem, although I never changed the config and the package was automatically pulled in. When I upgraded to the newer version i was asked several questions by (I guess) debconf. This way I could turn off the automatic start of the arrays (which I don't have) and now evertyhing works.
-- [Feisty]Can't start from lvm with mdadm version 2.5.5-1ubuntu2 https://launchpad.net/bugs/72494 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs