the answer is simple:
the dropdown doesn't work because there is a parent table in the 2nd site. try to add the red lines around your 1st site and you'll see, that it doesn't work with parent tables.
you have 3 options now:
a) find out if this dropdown-css works in span-classes or divs or whatever
b) use a simple non-table dropdown-list like suckerfish (http://www.alistapart.com/articles/dropdowns/)
c) use the existing script with tables and change all other content with removing any parent table
i suggest you to use b) and c) ! tables are not meant to be used for content or navigation. (http://www.hotdesign.com/seybold/) so change your design... replace every table with div and some css rules. it's not as hard as it sounds and it makes your site faster!