could not rename temporary statistics file: No such file or directory

I'm continuing to have file-access related errors with 8.1.5 on Windows.
(see my previous post here http://tinyurl.com/yfqhnm)

Today I'm having a new problem, which results in the following log
output:
2006-11-28 12:15:45 LOG: could not rename temporary statistics file
"global/pgstat.tmp" to "global/pgstat.stat": No such file or directory
2006-11-28 12:15:48 LOG: could not rename temporary statistics file
"global/pgstat.tmp" to "global/pgstat.stat": No such file or directory
2006-11-28 12:15:49 LOG: could not rename temporary statistics file
"global/pgstat.tmp" to "global/pgstat.stat": No such file or directory

There are no noticeable effects from these errors that I know of. I've
looked at file permissions, etc. and everything seems fine. I've got
FileMon running and don't see anything that is obviously related to
pgstat...

Any ideas what could cause this problem?

Jeremy Haile