code: protected Button newButton(final String id)
  	{
  		return new Button(id)
  		{
  			/** The serialVersionUID. */
  			private static final long serialVersionUID = 1L;
  
  			@Override
  			public void onSubmit()
  			{
  				onSignup(ComponentFinder.findOrCreateNewAjaxRequestTarget(), getForm());
  			}
  		};
  	}
docs: Factory method for creating the Button. This method is invoked in the constructor from the
  derived classes and can be overridden so users can provide their own version of a Button.
  
  @param id
  the wicket id
  @return the Button