>   | The only problem I can think of for something like qmail is if it does
>   | something like:
>   | 	write message to file
>   | 	fsync file
>   | 	rename file (to indicate that the file is a complete message)
>   | 	tell sender that the message has been received

> 
> That is almost certainly what it does, it is what sendmail does.

What recent versions of sendmail do is:

	write message to file
	fsync file
	rename file (to indicate that the file is a complete message)
	fsync file

[I know this because a recent tweak to softdeps broke this case for a
few days before it was fixed.. my laptop panic'ed every time i
attempted to send mail..]

If you add the second fsync to force the rename out to disk, you
should be all set..

						- Bill