$(document).delegate('.links', 'click', function(evt) {
    evt.preventDefault();
    var origanalUrl = $(this).attr('href');
    var hrefRegEx = /^(^/?{[A-Za-z_]*/?)?([A-Za-z_]+)(.php)$/
    var hashUrl2 = origanalUrl.replace(hrefRegEx, '$2');
    var hashUrl = '#' + hashUrl2;
        var urlExt = ' #ajaxTarget';
        var newUrl = origanalUrl + urlExt;
        if(!$(hashUrl).html() && hashUrl != '#index') {
            $(hashUrl).load(newUrl).ajaxComplete(function(event, XMLHttpRequest, ajaxOptions) {
                newMain = $(hashUrl);
                newHeight = newMain.outerHeight();
                alert(newHeight);
                $('#textBox_main').animate({
                    height: newHeight
                    }, 500, function() {
                    newMain.fadeIn(500);
                });
                oldMain = newMain;
            });
        } else {
            isLoaded = true;
        }

$(hashUrl).load(newUrl, function(response, status, xhr) {...} );

var fired = false;
$(document).delegate('.links', 'click', function(evt) {
    evt.preventDefault();
    var origanalUrl = $(this).attr('href');
    var hrefRegEx = /^(^/?{[A-Za-z_]*/?)?([A-Za-z_]+)(.php)$/
    var hashUrl2 = origanalUrl.replace(hrefRegEx, '$2');
    var hashUrl = '#' + hashUrl2;
        var urlExt = ' #ajaxTarget';
        var newUrl = origanalUrl + urlExt;
        if(!$(hashUrl).html() && hashUrl != '#index') {
            var ajax = $(hashUrl).load(newUrl);

            if (!fired) {
              ajax.ajaxComplete(function(event, XMLHttpRequest, ajaxOptions) {
                newMain = $(hashUrl);
                newHeight = newMain.outerHeight();
                alert(newHeight);
                $('#textBox_main').animate({
                    height: newHeight
                    }, 500, function() {
                    newMain.fadeIn(500);
                });
                oldMain = newMain;
              });
              fired = true;
            }
        } else {
            isLoaded = true;
        }