jQuery datepicker breaks with duplicate dom ids

Tabs and popups can mean several forms in the dom at once, and many forms have similar or the same names for elements. Unfortunately our quickform implementation uses the element name as the dom id, causing collisions. Aside from creating invalid markup, these collisions are usually harmless (browsers are good at handling invalid markup). But our implementation of jQuery datepicker and timepicker is very susceptible to breaking, and "start_date" and "end_date" are very common field names.