[Cialug] very odd email problem

[Hawkins]

CIALUG,

I have a friend who always gets two copies of every email I send him.

Oddly, it does not matter where I send them from, (home computer,home 
ISP, home email address, or work computer, work email address, work mail 
server..etc).

Nobody else gets two copies of email from me, in fact if I send email to 
my friends work email address he only gets one copy.

To make matters even more odd, he only gets two copies of email from me 
and no one else.

This apparently started about a month ago.

Any thoughts about where to start with this?

Steve
-- 
Stephen Hawkins NG0G
ng0g at mchsi.com
73 49 111 01001001