해당에러는 가우스 서비스소스상에서 writer에 가우스데이타셋이외의 자료가 쓰여질때 발생하는 에러인데,
이는 out.print등을 사용하신다든지, jsp 태그 열리고 닫힐때 공백이 있는 경우에 발생할수 있습니다.
예를들면 %>공백<%
에러가 발생하는 소스를 점검해보시기 바랍니다.

>게시판을 이용해 주셔서 감사합니다.
>다음양식에 맞게 입력해주세요.
>
>* 고객시스템명 : 온밀크
>* GAUCE 버전 :
>* WAS 종류(WebLogic 등등) : Tomcat 5.x
>* DB 종류 : MS-SQL2000
>* 문의 유형(질문/요청/참조) : 질문
>* 내용 :
>socket write error에 대해 자세히 설명해주셔서 감사합니다.
>
>이번에는 java.lang.IllegalStateException: getOutputStream() has already been called for this response
>이 Exception은 어떤 경우에 발생하고 어떻게 대처해야 할지 알려주세요.
>이 Exception도 socket write error 만큼이나 많이 발생하는군요...
>어찌됐건 서버의 로그 사이즈를 줄이라는 오더를 받아서.. --;;;
>아... 어렵습니다... (__) 도와주세요
>
>2005-11-30 09:42:14 StandardWrapperValve[jsp]: Servlet.service() for servlet jsp threw exception
>java.lang.IllegalStateException: getOutputStream() has already been called for this response
>        at org.apache.coyote.tomcat5.CoyoteResponse.getWriter(CoyoteResponse.java:599)
>        at org.apache.coyote.tomcat5.CoyoteResponseFacade.getWriter(CoyoteResponseFacade.java:163)
>        at org.apache.jasper.runtime.JspWriterImpl.initOut(JspWriterImpl.java:122)
>        at org.apache.jasper.runtime.JspWriterImpl.flushBuffer(JspWriterImpl.java:115)
>        at org.apache.jasper.runtime.PageContextImpl.release(PageContextImpl.java:190)
>        at org.apache.jasper.runtime.JspFactoryImpl.internalReleasePageContext(JspFactoryImpl.java:115)
>        at org.apache.jasper.runtime.JspFactoryImpl.releasePageContext(JspFactoryImpl.java:75)
>        at org.apache.jsp.service.close.smGetClose_005fnew_jsp._jspService(smGetClose_005fnew_jsp.java:313)
>        at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:94)
>        at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
>        at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:298)
>        at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
>        at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
>        at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
>        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:237)
>        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:157)
>        at com.imtsystem.framework.common.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:106)
>        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:186)
>        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:157)
>        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:214)
>        at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
>        at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
>        at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java:198)
>        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:152)
>        at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
>        at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
>        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:137)
>        at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
>        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:117)
>        at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:102)
>        at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
>        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
>        at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
>        at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
>        at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:929)
>        at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:160)
>        at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:793)
>        at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:702)
>        at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:571)
>        at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:644)
>        at java.lang.Thread.run(Thread.java:534)