Nice menus, problem expanding above 3 levels

Hi all,

I am using nice menus module for creating dynamic menus. Here i have menus which extend beyond 3 levels. Upto 3 levels its working very well. when i have fourth level submenu, all the fourth level submenus are showing up without hovering the mouse over them..I hope i am clear enough... Any help would be greatly appreciated.

Thanx in advance...