var gagent = navigator.userAgent;
var gpos = gagent.indexOf('MSIE');
if( gpos != -1) {
	gversion = parseFloat(gagent.substr(gpos+5,3));
	if(gversion < 7) {
		var imgarr = ['DrwImg1','DrwImg2','DrwImg3','DrwImg4'];
		var arrLength = imgarr.length;
		for(var i=0;i<arrLength;i++) {
			img = document.getElementById(imgarr[i]);
			img.src = img.src.substring(0,img.src.lastIndexOf('.')) + '.jpg';
		}
	}
}