diff --git a/maven-plugin-plugin/src/main/java/org/apache/maven/plugin/plugin/PluginReport.java b/maven-plugin-plugin/src/main/java/org/apache/maven/plugin/plugin/PluginReport.java
index 5394b33..95e67eb 100644
--- a/maven-plugin-plugin/src/main/java/org/apache/maven/plugin/plugin/PluginReport.java
+++ b/maven-plugin-plugin/src/main/java/org/apache/maven/plugin/plugin/PluginReport.java
@@ -64,7 +64,7 @@ public class PluginReport
      *
      * @parameter default-value="${project.build.directory}/generated-site/xdoc"
      */
-    private String outputDirectory;
+    private File outputDirectory;
 
     /**
      * Doxia Site Renderer.
@@ -128,7 +128,7 @@ public class PluginReport
     /** {@inheritDoc} */
     protected String getOutputDirectory()
     {
-        return outputDirectory;
+        return outputDirectory.getPath();
     }
 
     /** {@inheritDoc} */