php mail() with an incorrect date?

[partha]

this is for a legitimate todo/reminder app, NOT spam!

Is there a way to make an email message sent using PHP have a "sent date" at some point in the future?
In other words, I want PHP to send my message to [e-mail] right now, and arrive in mrx's inbox right now, but have his inbox say the message was sent on 1/23/08 or something.

[StupidScript]

Haven't tried it, but one of the SPAM tricks is to forge the mail headers ... quite simple, really. I don't know how your program would respond to a forged header, tho'.

Set your script to add a header like:

Date: Day, Mon DY YEAR HH:MM:SS PST\r\n

like

Date: Tue, Mar 18 1997 14:36:14 PST\r\n

at any time after the rest of the headers are added (i.e. after your BODY header). Mail will respond to pretty much any header in any order, using the last instance of a header as the primary. The above technique may end up using your forged Date header as the "real" Date header, since it will appear in the headers after the "real" Date header.