jQuery.fn.focusable = function(focusedClass, focusable) {

	if(!focusedClass) focusedClass = 'focused';
	if(!focusable) focusable = 'li';

	this.focus(function() {
		jQuery(this).parents().filter(focusable).addClass(focusedClass);
		});
	this.blur(function() {
		jQuery(this).parents().filter(focusable).removeClass(focusedClass);
		});

	};