diff --git a/eo/src/eoPop.h b/eo/src/eoPop.h
index bcd49c9f..b880717b 100644
--- a/eo/src/eoPop.h
+++ b/eo/src/eoPop.h
@@ -282,6 +282,13 @@ class eoPop: public vector<EOT>, public eoObject, public eoPersistent
   virtual string className() const {return "eoPop";};
     //@}
 
+  virtual void invalidate()
+  {
+    for (unsigned i=0; i<size(); i++)
+      this->operator[](i).invalidate();
+  }
+
+
  protected:
 
 };