The US House of Representatives has approved legislation to combat unsolicited commercial e-mails. The law - if passed by Senate - will require the sender to provide a valid return e-mail address.
This provision ensures that the recipients of unwanted messages, known as spam, can serve notice that they wish no further messages from the same source.
The legislation will also empower US ISPs to pursue offenders through the federal courts. Spammers could be fined $500 per message - up to a maximum of $50,000 for multiple offences.
The bill was passed by a huge majority of 427 to 1 and is expected to be greeted with similar approval when it goes before the Senate later this year.