i developing php based site. I use the code below to avoid user pressing back after logout:
header( "Last-Modified: " . gmdate( "D, j M Y H:i:s" ) . " GMT" );
header( "Expires: " . gmdate( "D, j M Y H:i:s", time() ) . " GMT" );
header( "Cache-Control: no-store, no-cache, must-revalidate" ); // HTTP/1.1
header( "Cache-Control: post-check=0, pre-check=0", FALSE );
header( "Pragma: no-cache" ); // HTTP/1.0
But, however this make my all forms reset when user press back. I want to do something like gmail style => if an user logged out i want to redirect him to a page, than from that page I want redirect to logout successful message page. So, user cannot press back button and return inside member area.