Mouseover Tabs Menu example not working!

1) Script Title:
Mouseover Tabs Menu

2) Script URL (on DD):
http://www.dynamicdrive.com/dynamici...seovertabs.htm

3) Describe problem:
I copied the css, js and htm file and some how feel that the given example does not work.

Then I copy the whole code directly from the source code and run it only to get an error. This occurs in line page_request.send(null) in line 81:

uncaught exception: [Exception... "Component returned failure code: 0x80520012 (NS_ERROR_FILE_NOT_FOUND) [nsIXMLHttpRequest.send]" nsresult: "0x80520012 (NS_ERROR_FILE_NOT_FOUND)" location: "JS frame :: javascript: eval(__firebugTemp__); :: anonymous :: line 1" data: no]

Line 0

Any help getting this working?

Regards
Krishna

I am really sorry about my earlier post, as I tried to include the submenucontents.htm as an .html file.

The code works absolutely fine!