Bug 146159 [Regression]Changing font operation doesn't work other than the first time
Description: The first time changing operation can work well. However, Change it again, it won't work. Steps: 1.Insert lable/text to layout or master page 2.Change the font from serif to cursive, it works well 3.Change the font again Result: The action doesn't work Additional infor: build number:200606080632
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/editors/schematic/editparts/ReportElementEditPart.java
{
			( (DesignElementHandle) getModel( ) ).removeListener( this );
		}
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.model.core.Listener#notify(org.eclipse.birt.model.core.DesignElement,
	 *      org.eclipse.birt.model.activity.NotificationEvent)
	 */
	public abstract void elementChanged( DesignElementHandle arg0,
			NotificationEvent arg1 );
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.gef.editparts.AbstractEditPart#createEditPolicies()
	 */
	protected abstract void createEditPolicies( );
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.gef.editparts.AbstractEditPart#getModelChildren()
	 */
	protected List getModelChildren( )
	{
		return super.getModelChildren( );
	}
	/*
	 * (non-Javadoc)
	 *