Description:
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Hi,

i'm having an issue with session_destroy();

This is a script sample:
$_SESSION['username'] = (isset($_POST['username']))? $_POST['username']: $_SESSION['username'];

In this case, after user login, than logout via session_destroy, if the user reloads the page, the first time the server raises this warning: 
Warning: Unknown: Your script possibly relies on a session side-effect which existed until PHP 4.2.3. Please be advised that the session extension does not consider global variables as a source of data, unless register_globals is enabled. You can disable this functionality and this warning by setting session.bug_compat_42 or session.bug_compat_warn to off, respectively. in Unknown on line 0

in var_dump i can see $_SESSION['username'] and $_SESSION['password'] to be unset after session_destroy. the second time, just reloading the page, these variables are set to NULL (correctly i think, missing the previous value for them). The third time the user may now access all contents as still logged in: i can  see the old variables values restored as before the session destroy, now!