var isIE = (navigator.appName == "Microsoft Internet Explorer");

window.onload = function () {
	if (!isIE) {
		
    	window.onblur = function() { onWindowBlur(); }
    	window.onfocus = function() { onWindowFocus(); }
	}
}

function onWindowFocus() {
	if (!isIE) {
		document.getElementById('shell').onFocus();
	}
}

function onWindowBlur() {
	if (!isIE) {
		document.getElementById('shell').onBlur();
	}
}