Description of problem:
Since F15 core, dracut has been using /run, but its "Requires: filesystem"
still accepts an old version of 'filesystem' without a /run directory.

Version-Release number of selected component (if applicable):
dracut-013-4.fc16
(and all versions back to dracut-009-10.fc15 (F15 core) inclusive)

How reproducible:
There will probably never be a problem in real life; only if one is
brave enough to upgrade to F15/F16 dracut on an F14 system.

Steps to Reproduce/Actual results:
With an initramfs generated by these dracut's, but on a system without
a /run directory, boot seems OK, but at shutdown there are repeated
messages: "umount: /run: not found" (and similar from umount2).
(There may well be messages at boot that I missed.  There is also a
bogus /run entry in /proc/mounts .)

Suggested fix:
Update the "Requires: filesystem" in dracut.spec to be:

    Requires: filesystem >= 2.4.39	# first appearance of /run

Additional info:
I grant that this is probably a moot point (not to be confused with
a mount point), but if the Requires is there at all it ought to be
correct.