fullscreen button not working: SWFTools + flowplayer3 (+ swfobject2 or not)

I have a drupal 6 install with Flowplayer 3, SWFTools and swfobject2.

On a page I use simple embed code :

<p>Video test</p>
<p><swf file="/media/myvideo.flv"> </swf></p>

Everything works beautifully in this regard. I can enable / disable the fullscreen button, modify various parameters using the SWFTools configuration page... yet, I cannot get the fullscreen button to work. Under the embedding setting I have 'Allow full screen mode' checked and all things seems as they should be.

Oddly, in another install with same configuration, the fullscreen button works... but I am not using the SWFObject2 embed method... I actually have a lot more code where I am passing the parameters and all this works well. This being said, the users managing this portion of the site won't be comfortable in posting and managing content via embed JS / flash code.

Should we not get the same functionality simply be selecting the right correct Embed options under SWFTools and Flowplaer2? Am I missing something?

Any help / leads / suggestions appreciated.