Dropdown Menu problem w/IE

Hi,
I downloaded a menu from an online bot for a site I am doing for a friend.
The main line of the menu has 7 items, and not all those items have secondary menu items, but some have 4 or more.. There is the problem..

The menu works perfect in Firefox, but in IE 7, when I get to the third secondary menu item down, the dropdown part disappears. I am clueless as to what is going on...

Example

Item1 Item2
subItemA
subItemB ( -> OK to this point)
subItemC ( -> the dropdown disappears here..)
subItemD

Any and all help is greatly appreciated..

Thanks,
Jake