Ext.Array.each(this.elements, function(element) {
                element.ajaxConfig = <element.currentAjaxConfig + defaultAjaxConfig>;
                //add to a "pendingElements" array
        });

start: function() {
        Ext.Array.each(pendingElements, function(element) {
                LoadManager.addTask(element);
                // You can put the "default config" here, as well...
                // Just patch element.ajaxConfig
                // You can EVEN save the old callback, if you thing there is one/it can do any good!
                var previousCallback = element.ajaxConfig.callback;
                element.ajaxConfig.callback = function() {
                                // make this element remove himself
                                LoadManager.removeTask(element);
                                previousCallback();
                        }
                Ext.Ajax.request(element.ajaxConfig);
        });
}

constructor: function() {
        Ext.Array.each(this.elements, function(element) {
                element.defaultAjaxConfig = {
                        callback: function() {
                                // make this element remove himself
                                LoadManager.removeTask(element);
                        }
                }
        });
},