Auto return from Paypal

i want that customer autmatically return to my site after paying at paypal. it is possible as i see such comments on another post but how is the problem??/ anyone know how to do it????

Log in to paypal
Click on "Profile"
Click on "Website Payment Preferences" (under "Selling Preferences" on the right)
Turn "Auto Return" on and use http://www.YOURSTORE.com/index.php?cont ... ut_success