Pixel font problem

I made a dynamic textfield that loads a html file.
I choose FFF Harmony from Fonts for Flash site as my font.
When i make a dynamic textfield and save it and view the text there is no problem but when i want to change the size of the dynamc textfield the sharpness of the pixel text is gone.
I use whole numbers for the X and Y and i embedded the font
What am i doing wrong ?