Problem getting a .mov file onto my .Mac HomePage

I'm using iMovie version 3.0.3, and exporting to 'QuickTime', format: Web.
I get as far as trying to choose the .mov file (.Mac account > HomePage > iMovie) and then get this message:

Safari cannot find the internet plug-in. The page "HomePage" has content of MIME type "image/x-quicktime", but you don't have a plug-in installed for this MIME type. A plug-in should be available on this page:
http://www.apple.com/quicktime/download/
Do you want to open the page?

Apart from the fact that this means absolutely nothing to me, when I visit the page in question it only seems to contain info about QuickTime itself. I am using QuickTime version 7.1.6 (reinstalled from the above link), and have QuickTime 7 Pro.
Can anyone help me find a way to get my .mov file onto my HomePage? Where can I get this plug-in, and what do I do with it once I've got it?