title: Cryptic jetty-maven-plugin error message 'ERROR: PWC6117: File "null" not found'
body: <p>I have a Maven Webapp producing a WAR file.
  I've just upgraded my Jetty plugin to the 7.4.2.v20110526 (from 6.x). I have the following set up:</p>
  
  <pre><code>        &lt;plugin&gt;
              &lt;groupId&gt;org.mortbay.jetty&lt;/groupId&gt;
              &lt;artifactId&gt;jetty-maven-plugin&lt;/artifactId&gt;
              &lt;version&gt;7.4.2.v20110526&lt;/version&gt;
  
              &lt;executions&gt;
                  &lt;execution&gt;
                      &lt;id&gt;jetty-run&lt;/id&gt;
  
                      &lt;phase&gt;package&lt;/phase&gt;
                      &lt;goals&gt;
                          &lt;goal&gt;run&lt;/goal&gt;
                      &lt;/goals&gt;
  
                      &lt;configuration&gt;
                          &lt;connectors&gt;
                              &lt;connector implementation="${connector}"&gt;
                                  &lt;port&gt;80&lt;/port&gt;
                                  &lt;maxIdleTime&gt;60000&lt;/maxIdleTime&gt;
                              &lt;/connector&gt;
                          &lt;/connectors&gt;
  
                          &lt;webAppConfig&gt;
                              &lt;contextPath&gt;/foo&lt;/contextPath&gt;
                          &lt;/webAppConfig&gt;
  
                          &lt;webappDirectory&gt;${project.build.directory}/foo&lt;/webappDirectory&gt;
  
                          &lt;scanIntervalSeconds&gt;10&lt;/scanIntervalSeconds&gt;
  
                          &lt;systemProperties&gt;
                              &lt;systemProperty&gt;
                                  &lt;name&gt;logback.configurationFile&lt;/name&gt;
                                  &lt;value&gt;file:${basedir}/target/${project.artifactId}-${project.version}/WEB-INF/classes/logback.xml&lt;/value&gt;
                              &lt;/systemProperty&gt;
                          &lt;/systemProperties&gt;
                      &lt;/configuration&gt;
                  &lt;/execution&gt;
              &lt;/executions&gt;
  
              &lt;dependencies&gt;
                  &lt;dependency&gt;
                      &lt;groupId&gt;log4j&lt;/groupId&gt;
                      &lt;artifactId&gt;log4j&lt;/artifactId&gt;
                      &lt;version&gt;1.2.13&lt;/version&gt;
                  &lt;/dependency&gt;
              &lt;/dependencies&gt;
          &lt;/plugin&gt;
  </code></pre>
  
  <p>For some unclear to me reason, I keep getting the cryptic error message below:</p>
  
  <pre><code>2011-07-07 11:51:16.431:WARN::Aliased resource: file:/java/foo/branches/stable/modules/foo-web/src/main/webapp/WEB-INF/jsps/main.jsp~=file:/java/foo/branches/stable/modules/foo-web/src/main/webapp/WEB-INF/jsps/main.jsp
  2011-07-07 11:51:16.507:WARN::Aliased resource: file:/java/foo/branches/stable/modules/foo-web/src/main/webapp/WEB-INF/jsps/main.jsp~=file:/java/foo/branches/stable/modules/foo-web/src/main/webapp/WEB-INF/jsps/main.jsp
  ERROR: PWC6117: File "null" not found
  </code></pre>
  
  <p>There is no exception, however I cannot log in to the webapp.</p>
  
  <p>However, if I grab the produced war file and deploy it into a clean Jetty installation, it works perfectly. What's the deal here...? I mean, this used to work with the 6.x plugin. No code changes whatsoever.</p>
  
  <p>The contents of the exploded directory are exactly the same as the ones in the war file - I checked -- there are no missing files or any obvious differences.</p>
  
  <p>This is a Spring Web project.</p>
  
  <p>Any ideas? Has anybody seen this before?</p>
  
  <p>Many thanks in advance!</p>