Cross-browser issue?

I have tried to make my Flash interface as fault tolerant as possible.

MovieClipLoader object is used to monitor if a dynamically loaded SWF fails (ie. if the SWF file is missing).

The above works when I preview the interface in IE (an error message is shown) but fails when in Firefox. In Firefox, a blank SWF is shown and I do not get an error message.

The SWFs that are loaded are in a folder that is below where the interface is loaded.

Any pointers?

Cheers
Alfred