Transparent swf in Powerpoint

Hello all!
I’m currently working on a corporate presentation in Powerpoint, as the client wants to have the possibility of adjusting slides and so. No problem at all, but I want to import swf movies into the powerpoint, and I want to have them a transparent background.

Is this possible? A quick search on kirupa showed me this
link, and on other sites I also found out that it might be possible with embedded html, but I dont think this is the right solution since there will not always be a inet connection. I also tried the flashtoolbar of internal support, but didnt worked. Grump.

Is it possible at all? I’m using powerpoint office 2007 and both flash 8 and flash cs3. Help would be appreciated.