diff --git a/org.apache.felix.framework/src/main/java/org/apache/felix/framework/ServiceRegistrationImpl.java b/org.apache.felix.framework/src/main/java/org/apache/felix/framework/ServiceRegistrationImpl.java
index f8a15a0..035eebd 100644
--- a/org.apache.felix.framework/src/main/java/org/apache/felix/framework/ServiceRegistrationImpl.java
+++ b/org.apache.felix.framework/src/main/java/org/apache/felix/framework/ServiceRegistrationImpl.java
@@ -97,6 +97,10 @@
             m_svcObj = null;
             m_factory = null;
         }
+        else
+        {
+            throw new IllegalStateException("Service already unregistered.");
+        }
     }
 
     //