Try adding the following to the JavaScript portion of the Resources section of the Export HTML5 with in5 dialog (in5 > Export HTML5 with in5... or in5 > Easy Export Wizard... and click on the Advanced button)
$(document).on('pageRendered', function(e, data) {
location.hash = 'p='+nav.current;
});
The above code is not recommended for use with the Slider Page Formats. For those, use this instead:
sliderSettings.hasTags = true;