function dc(encStr) {
	var s = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";

	var bits, decOut = '', i = 0;
	for(; i<encStr.length; i += 4) {
		bits = (s.indexOf(encStr.charAt(i)) & 0xff) <<18 | (s.indexOf(encStr.charAt(i +1)) & 0xff) <<12 | (s.indexOf(encStr.charAt(i +2)) & 0xff) << 6 | s.indexOf(encStr.charAt(i +3)) & 0xff;
    	decOut += String.fromCharCode((bits & 0xff0000) >>16, (bits & 0xff00) >>8, bits & 0xff);
	}
	if(encStr.charCodeAt(i - 2) == 61) undecOut=decOut.substring(0, decOut.length -2);
	else if(encStr.charCodeAt(i - 1) == 61) undecOut=decOut.substring(0, decOut.length -1);
	else undecOut=decOut;
  
	document.write(unescape(undecOut));		//line add for chinese 
}