Jonathan Hutchins wrote:

> My security system has caught three messages in the last two days with long, 
> random strings of letters in the subject header.  Is some sort of buffer 
> overflow exploit going around or something? 
> 

Tehy may be using this as an identifier string for spam.  If you view 
the msg. w/ embedded .jpg the mailclient identifies the message that is 
requesting the .jpg from a web server.  Then they look up your id string 
in a database and see that your email address is real.  Then more spam!!
Brian