Our improvements to Internet Mail, such as return receipts and spam relay
control, have quickly proliferated as de facto standards for the industry.
In all of these attacks, the systems becoming infected were then used as spam relays
for phishing attacks against Citibank.
Industry group Electronic Commerce Forum has published a white paper that calls for spammers to be subject to criminal law, especially if they take part in actions such as counterfeiting sender addresses and hacking servers for use as spam relays