Jquery level problem

I have a problem with my jQuery accordion plugin.
the control is always above everything in my page.
i try to change z-index but it not solve it.

this is the page:
http://www.hfx.com/en-US/General FAQs
If you try to press the top menu on:
"Trading Tools -> World Interest Rates"
you will find you can't do it, because the jQuery is above it.
I can't find anything about it in the web.
Someone?

Adi