problem in menu....

Question

Hai, I have created a Horizantal Drop down Menu using HTML and JavaScript in my WebApplication(like Infosys menu).Its working.When the mouse over to the main menu the submenu will be displayed and when the mouseout event occur the menu will be hided. I have Drop down combobox and Listboxes in the page.The problem is ,I am placing the mouse over the main menu and the submenu is displaying but the controls are displaying above the menu item. The submenu is displaying below the controls. I need the controls below and the menu above.To solve this,I changed the visibility of controls to hidden at mouseover event and changed the visibility true at mouseout event.It is not working good. ie,It is fliggering when moving the mouse over the dropdown submenus. I understand the problem that is when event changes from mouseover to mouseout this error happens..... I have also changed z-index but i did not get. Please give me the solution with some codes.......... Thanks....................