diff --git a/trunk/paradiseo-peo/src/core/eoVector_comm.h b/trunk/paradiseo-peo/src/core/eoVector_comm.h
index 5e867f1d9..9921c3622 100644
--- a/trunk/paradiseo-peo/src/core/eoVector_comm.h
+++ b/trunk/paradiseo-peo/src/core/eoVector_comm.h
@@ -43,7 +43,14 @@
 
 template <class F, class T> void pack (const eoVector <F, T> & __v) {
 
-  pack (__v.fitness ()) ;
+
+  if ( !__v.invalid() ) 
+  {
+	  pack( (unsigned int) 1 );
+      pack (__v.fitness ()) ;
+  }
+  else
+      pack( (unsigned int) 0 );
   unsigned len = __v.size ();
   pack (len);
   for (unsigned i = 0 ; i < len; i ++)
@@ -53,9 +60,15 @@ template <class F, class T> void pack (const eoVector <F, T> & __v) {
 template <class F, class T> void unpack (eoVector <F, T> & __v) {
 
   F fit; 
-  unpack (fit);
-  __v.fitness (fit);
-
+  unsigned int vfit;
+  unpack( vfit );
+  if ( vfit ) 
+  {
+  	  unpack (fit);
+      __v.fitness (fit);
+  }
+  else 
+      __v.invalidate();
   unsigned len;
   unpack (len);
   __v.resize (len);
diff --git a/trunk/paradiseo-peo/src/peoParaSGATransform.h b/trunk/paradiseo-peo/src/peoParaSGATransform.h
index 68f503b8b..81f3a724a 100644
--- a/trunk/paradiseo-peo/src/peoParaSGATransform.h
+++ b/trunk/paradiseo-peo/src/peoParaSGATransform.h
@@ -149,8 +149,8 @@ template< class EOT > void peoParaSGATransform< EOT > :: unpackResult() {
 	 :: unpack( pop->operator[]( sidx++ ) );
 	 :: unpack( pop->operator[]( sidx ) );
 	num_term += 2;
-	
-	if( num_term == pop->size() ) {
+	// Can be used with a odd size 
+	if( num_term == 2*(pop->size()/2) ) {
 
 		getOwner()->setActive();
 		resume();