Sub menu hiding behind dropdown menu

[marchmirchi]

I have vertical menu in my page and it has sub menu also. the menu work perfectly on all pages but whenever a page contain a dropdown menu in the middle of the page the sub hide behind the dropdown. Please check the URL for screen shot of this problem
Dropdown Screenshot

[konrad]

This problem occurs in Internet Explorer only. To prevent it, you can
hidie the dropdown or add an iframe
hope this helps