--- test/org/apache/catalina/startup/TestJspServlet.java	(revision 0)
+++ test/org/apache/catalina/startup/TestJspServlet.java	(revision 0)
@@ -0,0 +1,34 @@ 
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.catalina.startup;
+
+import java.io.File;
+
+public class TestJspServlet extends TomcatBaseTest {
+
+    public void testJspServlet() throws Exception {
+        Tomcat tomcat = getTomcatInstance();
+
+        File appDir = 
+            new File("test/webapp-2.3-jsp-servlet");
+        // app dir is relative to server home
+        tomcat.addWebapp(null, "/test", appDir.getAbsolutePath());
+        
+        tomcat.start();
+    }
+}
   + text/plain
   + native
--- test/webapp-2.3-jsp-servlet/WEB-INF/web.xml	(revision 1137791)
+++ test/webapp-2.3-jsp-servlet/WEB-INF/web.xml	(working copy)
@@ -29,4 +29,9 @@ 
     specification do not change the behaviour of applications that declared an
     earlier version of the specification. 
   </description>
-</web-app>
+  <servlet>
+    <servlet-name>ping</servlet-name>
+    <!-- doesn't have to be here to demonstrate bz 51396 -->
+    <jsp-file>/ping.jsp</jsp-file>
+  </servlet>
+</web-app>
--- java/org/apache/catalina/startup/ContextConfig.java	(revision 1137791)
+++ java/org/apache/catalina/startup/ContextConfig.java	(working copy)
@@ -1405,8 +1405,10 @@ 
         }
         servletDef.getParameterMap().put("jspFile", jspFile);
         servletDef.setJspFile(null);
-        for (Map.Entry<String, String> initParam: jspServletDef.getParameterMap().entrySet()) {
-            servletDef.addInitParameter(initParam.getKey(), initParam.getValue());
+        if (jspServletDef != null) {
+        	for (Map.Entry<String, String> initParam: jspServletDef.getParameterMap().entrySet()) {
+        		servletDef.addInitParameter(initParam.getKey(), initParam.getValue());
+        	}
         }
     }