I don't think you can but:
You can enter in "bind x say z" in the console
(without the quotes)
Where x is the key you want to bind to, and where z is what you want to say. So, when you die, just press whatever key you bind the message to, and then it will display it.
"700 years old, and still **** you up I can" -Yoda
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TheMadDoofer on WoW (Bloodscalp server), Call of Duty:UO, Battlefield 2,
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