weblogic下运行程序时，发生如下错误，请问是什么原因？
Error   500--Internal   Server   Error  
java.lang.IllegalArgumentException:   unsupported   encoding:   'null ':   java.io.UnsupportedEncodingException:   null
at   weblogic.servlet.internal.ServletResponseImpl.setEncoding(ServletResponseImpl.java:967)
at   weblogic.servlet.internal.ServletResponseImpl.setContentType(ServletResponseImpl.java:380)
at   weblogic.servlet.internal.ServletResponseImpl.setHeaderInternal(ServletResponseImpl.java:806)
at   weblogic.servlet.internal.ServletResponseImpl.setHeader(ServletResponseImpl.java:794)
at   jsp_servlet.__szaa0201._jspService(__szaa0201.java:164)
at   weblogic.servlet.jsp.JspBase.service(JspBase.java:34)
at   weblogic.servlet.internal.StubSecurityHelper$ServletServiceAction.run(StubSecurityHelper.java:214)
at   weblogic.servlet.internal.StubSecurityHelper.invokeServlet(StubSecurityHelper.java:120)
at   weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:272)
at   weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:165)
at   weblogic.servlet.internal.RequestDispatcherImpl.invokeServlet(RequestDispatcherImpl.java:504)
at   weblogic.servlet.internal.RequestDispatcherImpl.forward(RequestDispatcherImpl.java:245)
at   org.apache.struts.action.RequestProcessor.doForward(RequestProcessor.java:1062)
at   com.nec.jp.orteus.struts.RequestDispatchProcessor.doForward(RequestDispatchProcessor.java:929)
at   org.apache.struts.action.RequestProcessor.processForwardConfig(RequestProcessor.java:386)
at   com.nec.jp.orteus.struts.RequestDispatchProcessor.processForwardConfig(RequestDispatchProcessor.java:896)
at   com.nec.jp.orteus.struts.RequestDispatchProcessor.process(RequestDispatchProcessor.java:1465)
at   org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)
at   com.nec.jp.orteus.struts.RequestDispatchServlet.process(RequestDispatchServlet.java:222)
at   org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414)
at   javax.servlet.http.HttpServlet.service(HttpServlet.java:743)
at   javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
at   weblogic.servlet.internal.StubSecurityHelper$ServletServiceAction.run(StubSecurityHelper.java:214)
at   weblogic.servlet.internal.StubSecurityHelper.invokeServlet(StubSecurityHelper.java:120)
at   weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:272)
at   weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:165)
at   weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run(WebAppServletContext.java:3022)
at   weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321)
at   weblogic.security.service.SecurityManager.runAs(SecurityManager.java:121)
at   weblogic.servlet.internal.WebAppServletContext.securedExecute(WebAppServletContext.java:1925)
at   weblogic.servlet.internal.WebAppServletContext.execute(WebAppServletContext.java:1848)
at   weblogic.servlet.internal.ServletRequestImpl.run(ServletRequestImpl.java:1288)
at   weblogic.work.ExecuteThread.execute(ExecuteThread.java:207)
at   weblogic.work.ExecuteThread.run(ExecuteThread.java:179)
 


------解决方案--------------------
ServletResponseImpl.java的967行参数错误
------解决方案--------------------
应该是字符编码没有设置值吧。。。你现在的为空值。
------解决方案--------------------
在哪设置啊，楼上详细说明一下，是在weblogic.xml中么