DDLevelsmenu possible conflict with TabContent

1) Script Title: DDLevelsmenu

2) Script URL (on DD): http://www.dynamicdrive.com/dynamicindex1/ddlevelsmenu/

3) Describe problem:
When I also have tabcontent.js loaded on the same page (from http://www.dynamicdrive.com/dynamici...tabcontent.htm) I get a very odd thing with IE where it renders the DDLevels menu arrow twice and the drop down menus get messed up. When I remove tabcontent.js it then works fine. It seems as though something in tabcontent.js is calling the ddlevelsmenu function to render the arrows twice. This only seems to be a visual problem with IE. Other browsers seem to cope fine.