[Ex_Soft]

Разберитесь со statics

Ext.onReady(function() {
  Ext.define("TestClassWithStatics", {
    statics: {
      staticProp: "staticProperty"
    }
  });

  var
    o = Ext.create("TestClassWithStatics");

  alert(TestClassWithStatics.staticProp);
  alert(o.staticProp);
});

http://jsfiddle.net/ENqea/