using sessions

Hi, I am using sesion with php 4.0.2pl2. With that said this is where I am at. I have a page that when the user gets there sets a sesion id, whne the user goes to page two I call session_start() and then I can print out the session id no problem, if I go to the logout page which calls session_start(); and then session_destroy() and the back to the first session page we see that the session has indeed been destroyed. If I close the browser the session is gone as well. Now here is my question. I go to yahoo.com hit the back button and the session is still there. how do I remove the session if the user leaves my site? Thank you Ken -- I've got all the money I'll ever need if I die by 4 o'clock. -- Henny Youngman