I am now working on wiki, and want to embed a swf to a wiki page, by using embed tag which works well in IE, we can see it works well in Firefox when preview it rather than save, but when we save and close, it comes an error,"Please ensure the page source is valid XHTML. Switching to rich text mode from source mode will convert HTML to XHTML. ", and when i back to html source editor, we can see, the embed tag have changed to iframe, and i have looked thru lots of articles on internet, just didn't get any luck, so would anyone please help me out ?or , firefox doesn't support iframe perfectly, then, any suggestion?? thanks a lot in advance. Michale