I think you can able to generate read receipt requests for all kind of mail messages. For this you need to work on some manual by using OS X terminal.To do this
- Quit Mail and open command line terminal.
- Type the following text (keep all quote marks as mentionded there)
Code:
defaults write com.apple.mail UserHeaders '{"Disposition-Notification-To"="your@address";}'
Each and every one upcoming messages launched with Mail will currently comprise the Disposition-Notification-To header which one asking over for a return receipt. You can turn of this whenever you require. Type the following text in your terminal and it will disable this feature
Code:
defaults delete com.apple.mail UserHeaders
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