IE only JS errors

for some reason I keep getting javascript errors, but only in IE, any ideas? I’ve no idea how to even track it down since it works in everything else.

it especially breaks in ie 9, the menus.js doesn’t even work at all. it should hide the drop down menus, but doesn’t, and that is where ie tells me the error is. but everything looks fine?

http://www.tigerstudiodesign.com/sandbox/