让FireFox支持InnerText属性

if(window.navigator.userAgent.toString().toLowerCase().indexOf("firefox")>=0){
	// in firefox
	HTMLElement.prototype.__defineGetter__( "innerText",
		function(){
			var intxt = "";
			var ss = this.textContent.split("\n");
			for(var i=0; i <ss.length; i++){
			//处理空白字符
			intxt += ss[i].replace(/(^\s*)|(\s*$)/g, "");
			}
			return intxt;
		});
	HTMLElement.prototype.__defineSetter__( "innerText",
		function(sText){
			this.textContent=sText;
		});
}