diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectIdSubclassMap.java b/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectIdSubclassMap.java
index aa4bf99f3..612e00ea2 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectIdSubclassMap.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectIdSubclassMap.java
@@ -46,6 +46,7 @@
 package org.eclipse.jgit.lib;
 
 import java.util.Iterator;
+import java.util.NoSuchElementException;
 
 /**
  * Fast, efficient map specifically for {@link ObjectId} subclasses.
@@ -158,7 +159,7 @@ public V next() {
 						return v;
 					}
 				}
-				throw new IllegalStateException();
+				throw new NoSuchElementException();
 			}
 
 			public void remove() {