My c:\ is filling up with files like this:

s38c
s38c.1
s38c.1a
s38c.1b
etc...

Each of these files is not hidden, not system, and not read only.  However,
in normal windows mode I cannot copy, view, or delete these files (they are
owned by another process) but in safe mode I was able to view them, and
delete them.  

The file contains the text (including headers) of each email as it comes in.
Each file is a single email.  Each time Outlook 2003 receives new email, it
is copied here.  

Is this some kind of accidental logging feature I've enabled?

Any help greatly appreciated!