404 custom page on Win2000 server not working in frames

I have an entire site created in frames which is hosted on a Windows 2000 server (because my site uses MS Access database and asp)

I asked my hosting company to reconfigure the 404 customised error message handling to a page in my wwwroot folder (ie. same folder where the index.asp file resides)

I named the file notHere.htm (and now resides in the wwwroot folder)

When my hosting company set the redirection up, the 404 redirection to my new page worked fine when the misdirected address was outside the frames (ie. a normal page).

However, the problem was if the page to be loaded was inside the frameset, the site went crazy. It was if it was trying very hard to keep loading that page, notHere.htm, inside the frames at the right place but gave up after 10 or 12 seconds leaving the area completely blank.

The hosting company technical guy is as confused about this as I am. Can anyone help?

To recap:
--- If I directly type a URL in the browser for a page on my site that doesn't exist, the 404 redirection DOES WORK.

--- If I CLICK a LINK on my site that tries to load a page within the frameset that doesn't exist, the 404 page do NOT WORK.

I really need to get this working, so any help would be appreciated.

Best regards,

Chris.