embedFont causes text to disappear

Hi, I’ve been having this problem for a long time and i still cannot resolve it, before I’ve just found ways aroound it, if I have dynamically loaded text deom an XML document and I want to use a Font from my own library, I can’t because when i go to use the embedFonts statement it disappears, the everything else works fine, as long as i don’t use that command. I have set up the Font in the library, given it my own instance name but it will not work. has anyone else had a similar problem? here is the code if that might help…:

            target.createEmptyMovieClip("holderMain",target.getNextHighestDepth);
            target.holderMain.createTextField("my_txt",2,0,110,345,120)
            target.my_txt.selectable = false;
target.holderMain.my_txt.wordWrap = true;
            target.my_txt.border = false;
            myformat = new TextFormat();
            myformat.color = 0xFFFFFF;
            myformat.bullet = false;
            myformat.underline = false;
            myformat.font = "please";
            myformat.size = "10";
            target.holderMain.my_txt.htmlText = Math.floor((loadedBytes/totalBytes)*100);
            target.holderMain.my_txt.embedFonts = true;
            target.holderMain.my_txt.setTextFormat(myformat);

thanks if anyone can help…