On Tue, 10 Aug 2004 10:55:38 -0700, Randy Klumph <[log in to unmask]> wrote:

>my logs show no problem with his deliveries

Since you mention you are using LSMTP, have you done Site-Specific logging of
mail to his domain?

Or do the LSMTP Accounting.dat logs (assuming you are running Full Accounting)
show successful delivery for every message?

If either/both of above show positive delivery to his domain with no problems,
then supply him with the log segments showing same and let him take it up with
his ISP.