diff --git a/contribution/branches/PhyloMOEA/PhyloMOEA/PhyloMOEO_archive.h b/contribution/branches/PhyloMOEA/PhyloMOEA/PhyloMOEO_archive.h
index 8b352ff08..63fb70742 100644
--- a/contribution/branches/PhyloMOEA/PhyloMOEA/PhyloMOEO_archive.h
+++ b/contribution/branches/PhyloMOEA/PhyloMOEA/PhyloMOEO_archive.h
@@ -76,12 +76,12 @@ class PhyloMOEOFinalSolutionsArchive: public PhyloMOEOParetoSolutionsArchive
 {
   public:
 	// overwrite the default operator
-	void operator()(const eoPop < PhyloMOEO > & _pop) { update(_pop); }
+	bool operator()(const eoPop < PhyloMOEO > & _pop) { return update(_pop); }
   protected:
 
 
 
-	void update(const eoPop < PhyloMOEO > & _pop)
+	bool update(const eoPop < PhyloMOEO > & _pop)
 	{
 		
 		std::copy(_pop.begin(), _pop.end(), back_inserter(*this) );
@@ -111,6 +111,7 @@ class PhyloMOEOFinalSolutionsArchive: public PhyloMOEOParetoSolutionsArchive
 				}
 			}
 		}
+		return true;
    }
 };
 #endif