Hello! The issue mentioned on  happened on my system a few weeks ago. But now it seems that Debian Testing (Lenny) and Unstable (Sid) corrected this problem with sysvinit (2.86.ds1-47).
Perhaps you can add the distro to your list of fixed distros with updated shutdown. Regards Stephan Windmüller  http://linux-ata.org/shutdown.html  http://packages.debian.org/lenny/sysvinit
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