second INVALID email

[Ray Holme]

Whenever I submit an email to this group, I get a second email back immediately 
from the group (or maybe myself) with my full email address AND a tacked on 
.INVALID
i.e. the source is rayho...@yahoo.com.invalid
Is this standard for everyone, or did something happen when the daemon 
configured my email  or .... ???????
Not a problem, just confusing.