function erasearea(a){	if (a.value==a.defaultValue)		a.value="";}
function fillarea(a){	if (a.value=="")		a.value=a.defaultValue;}


function deselect(str_select){
	var obj_select = document.getElementById(str_select);
	for (var j=0; j < obj_select.options.length; j++) {
		obj_select.options[j].selected = false;
	}
}