[fckeditor] background-color in firefox

Hi,

I have a problem to add background-color to text from fckeditor in firefox (both linux and windows 1.0.7). I tried with IE 6 and it work well. I dont think the problem come from fckeditor itself because it work great in the demo http://www.fckeditor.net/demo/default.html . Did somebody already see this problem?

Thank you