Help with Autofilling Fields for Private Messages? Recipient, Title and Message Body

[CityGuard]

I'm trying to set up link for people to private message me about a certain subject and would like to have the PM title automatically filled in to make it easier to go through my messages.

Using the basic PM link http://www.EXAMPLESSITE.com/forum/private.php?do=newpm I'm able to specify the recipient by adding &u=NUMBER (where the number is the user ID number of the intended recipient).

I can't figure out what to add to autofill the "Title" (subject line) section. My best guesses, &title=TEXT &t=TEXT &subject=TEXT &s=TEXT didn't work.

Anyone know what to do here?

Also, is it possible to autofill in text for the message body? How do I accomplish that?