function validateNumeric(field) {
	var valid = "0123456789";
	if (field.length > 0) {
		for (var i=0; i < field.length; i++)
			{
			temp = "" + field.substring(i, i+1);
			if (valid.indexOf(temp) == "-1")
				{
				alert("Only numeric values are permitted in this field.");
				return false;
				}
			}
		}
	return true;
	}