function ClickDefaultButtonIfEnterKey(btn, event){
	if (document.all){
		if (event.keyCode == 13){
			event.returnValue=false;
			event.cancel = true;
			btn.click();
		}
	}
	else if (document.getElementById){
		if (event.which == 13){
			event.returnValue=false;
			event.cancel = true;
			btn.click();
		}
	}
	else if(document.layers){
		if(event.which == 13){
			event.returnValue=false;
			event.cancel = true;
			btn.click();
		}
	}
}