"LISTSERV list owners' forum" <[log in to unmask]> wrote on 
08/02/2005 04:06:58 PM:

> The man at the UK computing help desk said it was because of spam coming
> from those addresses. 

Earthlink is one of the more abused domain names (after AOL and hotmail) 
used by spammers when they forge emails.  Simply blocking all email 
because it comes from Eartlink is like setting up a road block and 
stopping anyone driving a Ford.