Dropdowns don't close on iPad once opened

I'm looking at  http://foundation.zurb.com/docs/components/dropdown-buttons.html and http://foundation.zurb.com/docs/components/dropdown.html

When you tap on a dropdown in iPad, it doesn't close if clicked anywhere outside the dropdown. You have to tap the same link or button.

I've tried this on an iPad 1 and an iPad 4. Desktop browser works fine as expected.

This is the pretty much the same as issue #1386 , which has been closed.