--- trunk/OOPSE/libmdtools/ZConstraint.cpp	2003/08/01 16:18:13	661
+++ trunk/OOPSE/libmdtools/ZConstraint.cpp	2003/08/08 17:48:44	671
@@ -491,6 +491,8 @@ template<typename T> void ZConstraint<T>::resetZ()
 
 template<typename T> void ZConstraint<T>::resetZ()
 {
+
+  double pos[3];
   double deltaZ;
   double mzOfZCons;   //total sum of m*z of z-constrain molecules
   double mzOfUncons; //total sum of m*z of unconstrain molecuels;
@@ -534,7 +536,9 @@ template<typename T> void ZConstraint<T>::resetZ()
     //update z coordinate    
     zconsAtoms = zconsMols[i]->getMyAtoms();    
     for(int j =0; j < zconsMols[i]->getNAtoms(); j++){
-      zconsAtoms[j]->setZ(zconsAtoms[j]->getZ() + deltaZ);  
+      zconsAtoms[j]->getPos(pos);
+      pos[2] += deltaZ;
+      zconsAtoms[j]->setPos(pos);  
     }    
     
     //calculate z constrain force