diff --git a/core/src/main/java/hudson/model/Queue.java b/core/src/main/java/hudson/model/Queue.java
index 6c5f4678b6..1ca6f1c45f 100644
--- a/core/src/main/java/hudson/model/Queue.java
+++ b/core/src/main/java/hudson/model/Queue.java
@@ -1505,12 +1505,16 @@ public class Queue extends ResourceController implements Saveable {
      */
     @ExportedBean(defaultVisibility = 999)
     public static abstract class Item extends Actionable {
-        /**
-         * VM-wide unique ID that tracks the {@link Task} as it moves through different stages
-         * in the queue (each represented by different subtypes of {@link Item}.
-         */
-	private final long id;
 
+        private final long id;
+
+        /**
+         * Unique ID (per master) that tracks the {@link Task} as it moves through different stages
+         * in the queue (each represented by different subtypes of {@link Item} and into any subsequent
+         * {@link Run} instance (see {@link Run#getQueueId()}).
+         * @return
+         * @since TODO
+         */
         @Exported
         public long getId() {
             return id;
diff --git a/core/src/main/java/hudson/model/Run.java b/core/src/main/java/hudson/model/Run.java
index 70189a8854..a45f8aeabb 100644
--- a/core/src/main/java/hudson/model/Run.java
+++ b/core/src/main/java/hudson/model/Run.java
@@ -139,6 +139,7 @@ public abstract class Run <JobT extends Job<JobT,RunT>,RunT extends Run<JobT,Run
 
     /**
      * The original {@link Queue.Item#getId()} has not yet been mapped onto the {@link Run} instance.
+     * @since TODO
      */
     public static final long QUEUE_ID_UNKNOWN = -1;
 
@@ -156,7 +157,7 @@ public abstract class Run <JobT extends Job<JobT,RunT>,RunT extends Run<JobT,Run
     /**
      * The original Queue task ID from where this Run instance originated.
      */
-    private long queueId;
+    private long queueId = Run.QUEUE_ID_UNKNOWN;
 
     /**
      * Previous build. Can be null.
@@ -428,7 +429,6 @@ public abstract class Run <JobT extends Job<JobT,RunT>,RunT extends Run<JobT,Run
      * <p/>
      * Mapped from the {@link Queue.Item#getId()}.
      * @param queueId The queue item ID.
-     * @since TODO
      */
     @Restricted(NoExternalUse.class)
     public void setQueueId(long queueId) {