If you mean have the menu item corresponding to the current page be selected, this really doesn't have anything to do with the script per say. What you're basically asking is how to apply some CSS class (ie: ".selected") to the link within the content DIVs that match up with the current page's URL. There is no mechanism within the script to do this matching, no. How it's usually done is via server side means, by dynamically adding ".selected" inside the HTML of the link that matches the current page's URL. There isn't a reliable way to do the match up using JavaScript, since many variations of a URL can in fact all mean the same URL, like:
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