This script will return a "receipt" to a send who asks for it.
(aka checks the "On Delivery Receipt" checkbox)
This is no a "On Read Receipt" and the return message CLEARLY
states that the message is to inform you that your message to $TO
has been recived and accepted by the server. But that does not mean
the user has Read the message or that the message has even been put
into the users mailbox.
1. Download all return-receipt file to your MailRoot/filters dir.
2. Add this to your filer.in.tab
3. restart xmail