Tab Navigation

[a.sh]

I have a horizontal menu with some menu items being inside <a> tag and two menu items in an applet tag. I need the user to be able to use the tab key to go through the menu items. I am able to tab through all the items inside the <a> tag, but I can't tab through the applet or the menu items in the applet.
I don't know if its possible to tab navigate through an applet?
I have attached a zip file including my html page.