Co***icting div layers and menu ... (w/Firefox)

[deltatango5]

http://www.deltatango5.com/TESTER6b.html

this is the link to reference ....... once you select a menu item: SERVICES and chose a link it of course populates the paired windows ... BUT when you go to GIFT IDEAS for instance, the menu appears until you mouse over ..... there is some kind of co***ict with the "content" window/div and the submenu ..... I for the life of me cannot find the issue--assistance is greatly appreciated.

NOTE: it works fine with IE ... FIREFOX is the issue ...

thanks in advance and happy new year!