.innerText dont work in firefox

var so = new SWFObject("playerSinglePackage/playerSingle.swf", "mymovie",
"192", "67", "7", "#FFFFFF");
var song1 ;
//only play in IE
if(document.all){
song1 = document.getElementById('abc').innerText;
}
else{
//song1 = document.getElementById('abc').innerText;
song1 = document.getElementById('abc').textContent;
}
so.addVariable("autoPlay", "no");
so.addVariable("soundPath", song1);
so.write("flashPlayer");