loopback won't unmount?!

[Net Llama!]

I mounted a ext3 filesystem image on loopback today, and then chroot'ed 
into it to make some changes.  when i tried to unmount it, it refuses 
with the error:
Device or resource busy

If i grep the output from lsof for the file that i had mounted, i get no 
results.  What can i do to unmount this besides rebooting the box?

-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
L. Friedman                       	       netllama at linux-sxs.org
Linux Step-by-step & TyGeMo: 		    http://netllama.ipfox.com

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