Why is a VerifyError thrown when publishing changes with a decorated HtmlResponseWriter
===

I am facing a problem when publishing changes to WebSphere with JSF2 (Myfaces 2.0.12).

Everytime I publish a change to my local server (WebSphere) I am getting a java.lang.VerifyError. After a full restart of the server the application runs smoothly with my changes.

    java.lang.VerifyError: com/sun/faces/renderkit/html_basic/HtmlResponseWriter.startElement(Ljava/lang/String;Ljavax/faces/component/UIComponent;)V

The StackTrace indicates that something is wrong with the ResponseWriter and indeed we changed a little bit there ;-)
For accessibility-reasons I have to have full controll of the HTML so I need custom HtmlRenderers. To reduce duplicate code I decorated the ResponseWriter I get from the FacesContext with my own, and provide additional convenience-methods on top.

    public class CustomResponseWriter<T extends UIInput & MyFormdataInterface> extends HtmlResponseWriter
    {
    
    	public CustomResponseWriter(ReponseWriter writer){
    		super(writer, writer.getContentType(), writer.getCharacterEncoding());
    	}
    
    	public writeFancy(T component)
    	{
		...
    		writeText(component.getMyFanceAttribute(), null);
		...
    	}
    }

As I said, the code runs fine after the server was restarted so I assume the code is correct. But on the other side, this error occurs only on pages where I use this CustomReponseWriter.

Is there anything wrong with the idea of decorating the ResponseWriter in a new class? Or might this just be a problem in WebSphere?