[development] Nice Menus problem

hi all I am a beginner to drupal development I am facing problem in implementing Nice Menus, things are going smooth in development of menus upto two levels of sub menus In detail I am trying to develop following menu structure About us --Introduction --Schemes ----National River Action Plan -----Objectives -----Guidelines ----National Lake Conservation Plan ------Objectives ------Guidelines and so on The things are ok upto level of National River Action Plan but when I move cursor over it, the options objectives and guidelines for both the menus aggregate together and not apperring as a sepaate one Please suggest me the way to solve the problem Thanks in advance -- अभिजीत किंजवडेकर