function checkZipcode(form){
	with(form){
		NumBtoS(zipcode);
		if(isNaN(zipcode.value) || zipcode.value=="" || zipcode.value.length!=5){
			alert('Please enter a valid 5-digit Zip Code');
			return false;
		}
		return true;
		
	}
}
function NumBtoS(obj){
	var tmp="";
	var tmpw;
	var ii;
	
	for(ii=0;ii<obj.value.length;ii++){
		tmpw=obj.value.charCodeAt(ii);
		if(tmpw>=65296 && tmpw<=65305){
			tmpw=String.fromCharCode(tmpw-65248);
			tmp=tmp + tmpw;
		}else{
			tmp=tmp + obj.value.charAt(ii);
		}
	}	
	obj.value=tmp;
}