I am looking to subclass RemoteObject. Instead of:

<mx:RemoteObject ... >
    <mx:method ... />
    <mx:method ... />
</mx:RemoteObject>

I want to do something like:

<remoting:CustomRemoteObject ...>
    <mx:method ... />
    <mx:method ... />
</remoting:CustomRemoteObject>

where CustomRemoteObject extends mx.rpc.remoting.mxml.RemoteObject like so:

package remoting
{
    import mx.rpc.remoting.mxml.RemoteObject;

    public class CustomRemoteObject extends RemoteObject
    {
        public function CustomRemoteObject(destination:String=null)
        {
            super(destination);
        }
    }
}

However, when doing so and declaring a CustomRemoteObject in MXML as above, the flex compiler shows the error:

Could not resolve <mx:method> to a component implementation

At first I thought it had something to do with CustomRemoteObject failing to do something, despite that (or since) it had no change except as to the name. So, I copied the source from mx.rpc.remoting.mxml.RemoteObject into CustomRemoteObject and modified it so the only difference was a refactoring of the class and package name. But still, the same error.

Unlike many MXML components, I cannot cmd+click <mx:method> in FlashBuilder to open the source. Likewise, I have not found a reference in mx.rpc.remoting.mxml.RemoteObject, mx.rpc.remoting.RemoteObject, or mx.rpc.remoting.AbstractService, and have been unsuccessful in find its source online.

Which leads me to the questions in the title: