Under Internet Explorer 8, everything works as expected.
Under Firefox 3.6.6 and Chrome 4.1 any time a link is clicked on the site (and the link isn't listed on a menu or sidebar) the is_user_logged_in() function always returns false.
Here's what I'm doing. On http://www.backtolifemeditations.com I've created a custom header menu that will direct logged in users to a different product page than those not logged in.
This product page contains links to other products.
If you click on one of these links using Firefox or Chrome, the Logout button switches to a Login button and the custom menu directs to the wrong page.
I've been troubleshooting this for a couple hours and can't figure this out. If I add one of the product pages to the sidebar or header menu's the behavior is resolved. However I can't have the menus cluttered with every product page.