Parameters in PHP email script
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I have written a php email script, Message from our Site suppose `My~PHP~Script.com` is sent to user eg: `abc@yahoo~mail.com` from eg: `def@yahoo~mail.com` in a particular format:

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`Subject: def@yahoo~mail.com sent you a message Via My~PHP~Script~`

`From: noreply@My~PHP~Script.com`

`Message: Here is the message....`

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Now I want that in Yahoo Mail (or in any other mail) if the person (`abc@yahoo~mail.com`) clicks on `Reply to mail` then Yahoo or (other mail sites) should pick up the email from subject (i.e. `def@yahoo~mail.com`) for replying.

Do I need to send any specific parameters to inform mail sites that at which address user can reply.... How to achieve the desired results...?
