title: Classpath empty when adding <outputDirectory> to pom
body: <p>I am using this simple <code>pom.xml</code> to generate an OSGi-bundle using the <code>maven-bundle-plugin</code>:</p>
  <pre><code>&lt;project xmlns=&quot;http://maven.apache.org/POM/4.0.0&quot; 
           xmlns:xsi=&quot;http://www.w3.org/2001/XMLSchema-instance&quot;
           xsi:schemaLocation=&quot;http://maven.apache.org/POM/4.0.0 
                               http://maven.apache.org/xsd/maven-4.0.0.xsd&quot;&gt;
      &lt;modelVersion&gt;4.0.0&lt;/modelVersion&gt;
      &lt;groupId&gt;de.test.osgi&lt;/groupId&gt;
      &lt;artifactId&gt;test&lt;/artifactId&gt;
      &lt;version&gt;0.0.1-SNAPSHOT&lt;/version&gt;
      &lt;packaging&gt;bundle&lt;/packaging&gt;
      &lt;build&gt;
          &lt;plugins&gt;
              &lt;plugin&gt;
                  &lt;groupId&gt;org.apache.felix&lt;/groupId&gt;
                  &lt;artifactId&gt;maven-bundle-plugin&lt;/artifactId&gt;
                  &lt;version&gt;2.3.7&lt;/version&gt;
                  &lt;extensions&gt;true&lt;/extensions&gt;
              &lt;/plugin&gt;
          &lt;/plugins&gt;
      &lt;/build&gt;
  &lt;/project&gt;
  </code></pre>
  <p>This works as expected (that project contains a single public class that I have verified to be exported in the bundle). Now , if I add the following <code>&lt;configuration&gt;</code> to the plugin:</p>
  <pre><code>&lt;configuration&gt;
      &lt;outputDirectory&gt;D:\Test&lt;/outputDirectory&gt;
  &lt;/configuration&gt;
  </code></pre>
  <p>the build fails with the following error:</p>
  <pre><code>[INFO] --- maven-bundle-plugin:2.3.7:bundle (default-cli) @ test ---
  [WARNING] Bundle de.test.osgi:test:bundle:0.0.1-SNAPSHOT : Classpath is empty. Private-Package and Export-Package can only expand from the classpath when there is one
  [WARNING] Bundle de.test.osgi:test:bundle:0.0.1-SNAPSHOT : Instructions in Private-Package, or -testpackages that are never used: .*
  Classpath: 
  [ERROR] Bundle de.test.osgi:test:bundle:0.0.1-SNAPSHOT : The JAR is empty: dot
  [ERROR] Error(s) found in bundle configuration
  [INFO] ------------------------------------------------------------------------
  [INFO] BUILD FAILURE
  [INFO] ------------------------------------------------------------------------
  [INFO] Total time: 0.891s
  [INFO] Finished at: Fri Mar 30 14:49:46 CEST 2012
  [INFO] Final Memory: 8M/20M
  [INFO] ------------------------------------------------------------------------
  [ERROR] Failed to execute goal org.apache.felix:maven-bundle-plugin:2.3.7:bundle (default-cli) on project test: Error(s) found in bundle configuration -&gt; [Help 1]
  </code></pre>
  <p>Why is the classpath empty? What does the <code>&lt;outputDirectory&gt;</code> have to do with it? Is this a bug, or have I misunderstood something?</p>
  <p><strong>Edit</strong>
  Running with debug-output reveals that the classpath is indeed identical with <code>&lt;outputDirectory&gt;</code>. By default, this is mavens <code>target</code> directory, so he will find the classes to include in the bundle there. If I change it, it will point to a directory that contains no classes to include. Confusingly, the <a href="http://svn.apache.org/repos/asf/felix/releases/maven-bundle-plugin-2.3.7/doc/site/bundle-mojo.html" rel="nofollow noreferrer">documentation for the plugin</a> says that <code>&lt;outputDirectory&gt;</code> is:</p>
  <blockquote>
  <p>The directory for the generated bundles.</p>
  </blockquote>
  <p>Is this a mistake?</p>