Objectivec 无法在 Interface Builder (Xcode 5) 中创建与子视图的出口连接

I know this appears to be a duplicate of some other questions, but the answers are not working for me.

1. I have created a single view app.
2. In the storyboard I added a subview to my main view.
3. I have a label on my main view and another label on my subview.
4. I have created a class of type UIView and added it as the custom class for the subview.
5. I can ctrl-drag my label on my main view to the main view controller class. But when I try to ctrl-drag my label on my subview to my custom class, I cannot get the connection to occur.
6. I have even typed the property information and tried to make the connection manually to no avail.

Things have changed a bit in the latest version of Xcode's Interface Builder. Can somebody tell me what I am missing? There is literally no code here. I am just testing trying to connect outlets to a subview with a custom class.

The first image shows that I have set up the custom class and added a property but I cannot make the connection.

The second image shows the main view label is connected in the main view's controller.

The third image shows that there are no outlet connections for the subview's label.