Index: kernel/src/optimizers/MolecularDynamics.cpp
===================================================================
--- kernel/src/optimizers/MolecularDynamics.cpp	(revision 447)
+++ kernel/src/optimizers/MolecularDynamics.cpp	(working copy)
@@ -54,8 +54,8 @@
 
   for (unsigned int i = 0; i < get_model()->number_of_particles(); ++i) {
     Particle *p = get_model()->get_particle(i);
-    if (p->has_attribute(cs_[0]) && p->get_is_optimized(cs_[2])
-        && p->has_attribute(cs_[1]) && p->get_is_optimized(cs_[2])
+    if (p->has_attribute(cs_[0]) && p->get_is_optimized(cs_[0])
+        && p->has_attribute(cs_[1]) && p->get_is_optimized(cs_[1])
         && p->has_attribute(cs_[2]) && p->get_is_optimized(cs_[2])
         && p->has_attribute(masskey_) && !p->get_is_optimized(masskey_)) {
       add_particle(p);
@@ -135,7 +135,9 @@
 
     ekinetic += mass * (vx * vx + vy * vy + vz * vz);
   }
-  return 0.5 * ekinetic * conversion;
+
+  float ret= 0.5 * ekinetic * conversion;
+  return ret;
 }
 
 Float MolecularDynamics::get_kinetic_temperature(Float ekinetic) const
@@ -146,7 +148,8 @@
     // E = (n/2)kT  n=degrees of freedom, k = Boltzmann constant
     // Boltzmann constant, in kcal/mol
     const Float boltzmann = 8.31441 / 4186.8;
-    return 2.0 * ekinetic / (degrees_of_freedom_ * boltzmann);
+    float ret= 2.0 * ekinetic / (degrees_of_freedom_ * boltzmann);
+    return ret;
   }
 }
 
Index: kernel/test/optimizers/test_md_optimizer.py
===================================================================
--- kernel/test/optimizers/test_md_optimizer.py	(revision 447)
+++ kernel/test/optimizers/test_md_optimizer.py	(working copy)
@@ -129,6 +129,8 @@
         ekinetic = self.md.get_kinetic_energy()
         tkinetic = self.md.get_kinetic_temperature(ekinetic)
         diff = abs(tkinetic - desired)
+        print diff
+        print tolerance
         self.assert_(diff < tolerance)
 
     def test_temperature(self):
@@ -148,7 +150,7 @@
         self.md.assign_velocities(100.0)
         ekinetic = self.md.get_kinetic_energy()
         self.assertNotEqual(ekinetic, 0.0)
-        self._check_temperature(100.0, 10.0)
+        self._check_temperature(100.0, 20.0)
 
     def test_rescaling(self):
         """Test thermostatting by velocity rescaling"""