Drop down menu on SWC website not behaving as expected on mobile browsers

There seems to be a bug in the behaviour of the drop-down nav menu for the Software Carpentry website under Safari on an iPhone running iOS 6.0.1.

Clicking on the icon renders the menu top-level labels as expected, and touching the label (e.g. Boot Camps) expands out the next level labels properly.

However, if you try and press one of these labels (e.g. Upcoming Boot Camps), instead of loading that page, it acts as if you had pressed the top-level label that would have been in that area of the screen previously (in this case Badges).

**This means you can't get to the page you want to using the drop down menu, and therefore can't get to any page not linked in the body without resorting to a search engine or direct URL, on an iPhone**

It appears to afflict all browsers based on Apple's default iOS webkit implementation on an iPhone (I haven't tried on an iPad or Android device). The bug appears to be consistent across pages and menu items on the site.