> I guarantee Hotmail will destroy the original document [containing HTML/CSS and/or JavaScript] and do so in such a way that the document evolves from machine

> I guarantee Hotmail will destroy the original document [containing HTML/CSS and/or JavaScript] and do so in such a way that the document evolves from machine that touches the document. I'm not disagreeing with you here and you're most likely correct. Exchange has historically not complied with SMTP RFCs. I'll try it out and see how it changes just to satisfy my curiosity. I suspect that you were to send email like you specified through Postfix, Sendmail, or Exim, it wouldn't be altered before being sent to the next MTA or delivered to the user's mailbox.