Sending confirmation Email

[predators]

I have written a form script that submits the form data to me.  This part works fine.  I also want to send the sender a confirmation e-mail.  I have written this part of the code also, but the from line in the confirmation e-mail is the e-mail of the ISP and not mine.  Any suggestions?

[schilly]

mail($to_address,$subject,$body,"FROM: $from_address\r\n");