java.lang.IllegalStateException: sendError() forbidden after buffer has
been committed.
	at com.caucho.server.connection.AbstractHttpResponse.sendError(AbstractHttpResponse.java:468)
	at com.caucho.server.connection.AbstractHttpResponse.sendError(AbstractHttpResponse.java:455)
	at com.caucho.servlets.FileServlet.service(FileServlet.java:266)
	at com.caucho.server.dispatch.ServletFilterChain.doFilter(ServletFilterChain.java:106)
	at com.caucho.server.webapp.DispatchFilterChain.doFilter(DispatchFilterChain.java:115)
	at com.caucho.server.dispatch.ServletInvocation.service(ServletInvocation.java:229)
	at com.caucho.server.webapp.RequestDispatcherImpl.forward(RequestDispatcherImpl.java:277)
	at com.caucho.server.webapp.RequestDispatcherImpl.error(RequestDispatcherImpl.java:113)
	at com.caucho.server.webapp.ErrorPageManager.sendServletError(ErrorPageManager.java:362)
	at com.caucho.server.webapp.WebAppFilterChain.doFilter(WebAppFilterChain.java:175)
	at com.caucho.server.dispatch.ServletInvocation.service(ServletInvocation.java:229)
	at com.caucho.server.http.HttpRequest.handleRequest(HttpRequest.java:274)
	at com.caucho.server.port.TcpConnection.run(TcpConnection.java:514)
	at com.caucho.util.ThreadPool.runTasks(ThreadPool.java:520)
	at com.caucho.util.ThreadPool.run(ThreadPool.java:442)
	at java.lang.Thread.run(Thread.java:662)