c # – Subscribe to a custom event in an unrelated UserControl

I have a custom event set in a Form that I want to subscribe to a non-related (that is, not a child of this form) UserControl.
As it stands, the event is never dealt with in the UserControl
What do I miss?

EventTopicNames.cs

Public class EventTopicNames
{
constant public string ApplicationClosing = "ApplicationClosing";
}

ShellForm.cs

public partial class ShellForm: System.Windows.Forms.Form

        [Microsoft.Practices.CompositeUI.EventBroker.EventPublication (Interface.Constants.EventTopicNames.ApplicationClosing, Microsoft.Practices.CompositeUI.EventBroker.PublicationScope.Global)]
        public event System.EventHandler ApplicationClosing;

internal virtual void protected OnApplicationClosing (System.EventArgs eventArgs)
{
if (this.ApplicationClosing! = null)
{
this.ApplicationClosing (this, eventArgs);
}
}

UnrelatedUserControl.cs

public partial class UnrelatedUserControl: System.Windows.Forms.UserControl
{
     [Microsoft.Practices.CompositeUI.Commands.CommandHandler(Infrastructure.Interface.Constants.EventTopicNames.ApplicationClosing)]
    Internal Virtual Void Protected OnApplicationClosing (Object Sender, Infrastructure.Interface.EventArgs eventArgs)
{
// do things but never called
}
}