mdadm in maverick is a very old version, which was last updated in Dec 2010. So if it worked in Lucid, then on the surface of it, the regression seems unlikely to be in mdadm. Here is the last debian/chanagelog entry
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mdadm (2.6.7.1-1ubuntu15) lucid; urgency=low
* Rename debian/mdadm.vol_id.udev to debian/mdadm.mdadm-blkid.udev so that
the rules file ends up with a more reasonable name following changes in
debhelper 7.4.2, and adjust the initramfs hook to match (LP: #493772).
* Build-depend on debhelper 7.4.2.
-- Colin Watson <email address hidden> Sat, 12 Dec 2009 14:36:53 +0000
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mdadm in maverick is a very old version, which was last updated in Dec 2010. So if it worked in Lucid, then on the surface of it, the regression seems unlikely to be in mdadm. Here is the last debian/chanagelog entry
------------
mdadm (2.6.7.1-1ubuntu15) lucid; urgency=low
* Rename debian/ mdadm.vol_ id.udev to debian/ mdadm.mdadm- blkid.udev so that
the rules file ends up with a more reasonable name following changes in
debhelper 7.4.2, and adjust the initramfs hook to match (LP: #493772).
* Build-depend on debhelper 7.4.2.
-- Colin Watson <email address hidden> Sat, 12 Dec 2009 14:36:53 +0000
------------