function areaCodes(http_request,divID) {
    if (http_request.status == 200) {
        var aDiv = document.getElementById(divID);
        var response = http_request.responseXML.documentElement;
        var numElements = response.getElementsByTagName('x').length;
        var facField = document.myForm.fac.value;
        var theCode = new Array(numElements);
        var theLoc = new Array(numElements);
        var foundItFlag = false;
        for(var i = 0; i < numElements; i++){    
            theCode[i] = response.getElementsByTagName('ac')[i].firstChild.data;
            theLoc[i] = response.getElementsByTagName('loc')[i].firstChild.data;
            if(facField == theCode[i]) {
                foundItFlag = true;
                aDiv.innerHTML = theLoc[i];
                break;
            }
        }
        if(!foundItFlag) {
            aDiv.innerHTML = 'Not found.';
        }
    } else {
        aDiv = document.getElementById(divID);
        aDiv.innerHTML = 'Error in areaCodes.js - Could not access XML data.' + http_request.status;
    }
    aDiv = null;
}