function chkZipCodeTxt() {
	var obj = document.getElementById("center_search");
	if ( obj["zipcode"].value.length < 1 || obj["zipcode"].value == "Zip Code") {
		obj["zipcode"].value=''
	}
}

function chkZipCodeEmpty() {
	var obj = document.getElementById("center_search");
	if ( obj["zipcode"].value.length < 1 ) {
		obj["zipcode"].value = "Zip Code"
	}
}