Ever had an email that you sent to a Blackberry user, and they said, “I never got it”? By using a neat little trick, you can tell if they are telling you the truth about that or not!
Similar to the delivery receipt in Exchange, Blackberry devices have their own built in confirmation system. Simply put <confirm> in the subject line, followed by your original subject.
You will receive an email back, if the device received the email, giving you proof that the message was delivered successfully. So next time you have to email a blackberry user, CYA… 
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