Uso Jasper com Struts 2 dando erro java.lang.IllegalStateException: getOutputStream() has already be

private String  geracao () throws XXXXException, IOException{
OutputStream ops = null;  


	response.setContentType(CONTENT_TYPE_PDF);   
  			byte[] bytes = JasperRunManager.runReportToPdf(jasperURL.openStream(), parameters, con);   
  			if (bytes != null) {   
		             ops = response.getOutputStream();   
		             System.out.println("Writting binary");   
		             ops.write(bytes);   
		             System.out.println("Sending report...");   
		     }   

	}finally{
			 if (ops != null) {
	 	            ops.flush();
	 	            ops.close();
	 	            dbmanager.close();
 	         }
		}

20/02/2009 17:26:55 org.apache.catalina.core.ApplicationDispatcher invoke
SEVERE: Servlet.service() for servlet jsp threw exception
java.lang.IllegalStateException: getOutputStream() has already been called for this response
	at org.apache.catalina.connector.Response.getWriter(Response.java:610)
	at org.apache.catalina.connector.ResponseFacade.getWriter(ResponseFacade.java:198)
	at javax.servlet.ServletResponseWrapper.getWriter(ServletResponseWrapper.java:112)
	at org.apache.jasper.runtime.JspWriterImpl.initOut(JspWriterImpl.java:125)
	at org.apache.jasper.runtime.JspWriterImpl.flushBuffer(JspWriterImpl.java:118)
	at org.apache.jasper.runtime.JspWriterImpl.write(JspWriterImpl.java:326)
	at org.apache.jasper.runtime.JspWriterImpl.write(JspWriterImpl.java:342)
	at org.apache.jsp.decorators.ims_jsp._jspService(ims_jsp.java:260)
	at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
	at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:374)
	at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342)
	at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:630)
	at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:535)
	at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:472)
	at com.opensymphony.module.sitemesh.filter.PageFilter.writeDecorator(PageFilter.java:173)
	at com.opensymphony.module.sitemesh.filter.PageFilter.applyDecorator(PageFilter.java:158)
	at com.opensymphony.module.sitemesh.filter.PageFilter.doFilter(PageFilter.java:62)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
	at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845)
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
	at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
	at java.lang.Thread.run(Unknown Source)
20/02/2009 17:26:55 org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet default threw exception