Flash 5 - preloader and animation for external swf's

Hi,

I need to create a preloader that loads external swf files, but instead of counting values etc, rather have some animated doors slide over the top of the MC that the external swf is loading into.

When the external swf is loaded, I want the sliding doors (or image or whatever) to open back up and reveal the loaded movie.

I found a Flash MX version of this on the Kirupa site, but cannot find a Flash 5 version. I know it can be done in Flash 5 cos’ I have seen sites that utilised it before MX came out.

Thanks in advance,