diff --git a/core/src/main/java/hudson/tasks/junit/PackageResult.java b/core/src/main/java/hudson/tasks/junit/PackageResult.java
index 46f17bb6e500a06af9265d9ecdb1157126c823d2..1cb604308e9b43a58fd051abf11f85c28e7f9a55 100644
--- a/core/src/main/java/hudson/tasks/junit/PackageResult.java
+++ b/core/src/main/java/hudson/tasks/junit/PackageResult.java
@@ -17,7 +17,7 @@ import java.util.TreeMap;
  *
  * @author Kohsuke Kawaguchi
  */
-public final class PackageResult extends MetaTabulatedResult {
+public final class PackageResult extends MetaTabulatedResult implements Comparable<PackageResult> {
     private final String packageName;
 
     /**