Unreferenced files not being deleted

On my recent -current, I've noticed that /var is filling up with
unreferenced files.  I think I've noticed this with some other
partitions but they aren't as active and I didn't check carefully.
fstat(8) and lsof both agree that the files are not open and I've
unmounted all nfs clients.  I don't think it happens to all files,
I suspect (but haven't confirmed) that it happens when an open
file is deleted and then closed.

I've noticed this for a while on crashes but assumed it was just
processes keeping open files around.  fsck seems to clean up the
files but in the case of /var, this basically means rebooting the
system.

Has anyone else seen anything similar to this?

-- 
Peter Jeremy