The problem is that the request is not even reaching my method for generating the chart. It crashes when trying to get the outputStream (maybe a question for rich faces guys). The ajax4jsf tag need to have a method with the following parameters: genChart(OutputStream out, Object value) So I think I've misconfigured something, because org.ajax4jsf.resource.FacesResourceContext.getOutputStream lookup the stream on ResourceResponseImpl.getOutputStream instead of ResourceResponseImpl.getPortletOutputStream. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4251033#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...