Javascript differences between IE and Firefox

I have a live site which is working fine except for one problem: Drop down menus work fine in Firefox but stop working in IE on some pages.

This is the site:

[url removed, login to view]

On this page, menus work fine and functionality works fine:

[url removed, login to view]

But in this page, the menu no longer drops down in IE (OK in Firefox)

[url removed, login to view]

I think (I could be wrong) that the problem is that the first page uses [url removed, login to view], and the second page uses pop-closeup-2.js. And I need the functionality in [url removed, login to view] to make the page work - it is what makes the big image swap out when you click the small images.

So, I am out of my depth on the javascript, but open to help. Any offers? I'll try and upload a zip of the whole site.

## Deliverables

1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done.

2) Deliverables must be in ready-to-run condition, as follows (depending on the nature of the deliverables):

a) For web sites or other server-side deliverables intended to only ever exist in one place in the Buyer's environment--Deliverables must be installed by the Seller in ready-to-run condition in the Buyer's environment.

b) For all others including desktop software or software the buyer intends to distribute: A software installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request.

3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement).

## Platform

IE 6.0 AND Firefox

Engineering MySQL PHP Software Architecture Software Testing User Interface / IA

Project ID: #3472879

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