This tip is great for use with Joomla and mmenu.
@micha149 has shown me this jQuery snippet which will catch all absolute and relative URLs.
var url = window.location.href; // Will only work if string in href matches with location
$('.menu a[href="'+ url +'"]').addClass('active');
// Will also work for relative and absolute hrefs
$('.menu a').filter(function() {
return this.href == url;
}).addClass('better-active');
http://www.paulund.co.uk/use-jquery-to-highlight-active-menu-item