diff --git a/HLT/Trigger/TrigTransforms/TrigTransform/python/dbgHltResult.py b/HLT/Trigger/TrigTransforms/TrigTransform/python/dbgHltResult.py
index 9907106f7aaf7b95885bb3f2ff32b26f1f3f438a..38b4f4c73ed582a523baa3d5beceb9d68caf1d52 100644
--- a/HLT/Trigger/TrigTransforms/TrigTransform/python/dbgHltResult.py
+++ b/HLT/Trigger/TrigTransforms/TrigTransform/python/dbgHltResult.py
@@ -13,10 +13,9 @@ from CLIDComps.clidGenerator import clidGenerator
 
 clidg = clidGenerator("")
 
-cppyy.makeNamespace('HLT')
-ActualHLTResult = cppyy.makeClass('HLT::HLTResult')
 
-stringSerializer = cppyy.makeClass('StringSerializer')()
+ActualHLTResult=ROOT.HLT.HLTResult
+stringSerializer = ROOT.StringSerializer()
 
 class hltResult(ActualHLTResult):
   def __init__(self):
diff --git a/Simulation/G4Atlas/G4AtlasApps/python/AtlasG4Eng.py b/Simulation/G4Atlas/G4AtlasApps/python/AtlasG4Eng.py
index 79ca411dfe1351ae8e9aefa73b6e442dfc970250..c0e4dac47bd5e6b4442097111d589c89ce3962c9 100644
--- a/Simulation/G4Atlas/G4AtlasApps/python/AtlasG4Eng.py
+++ b/Simulation/G4Atlas/G4AtlasApps/python/AtlasG4Eng.py
@@ -18,7 +18,7 @@ from AthenaCommon.SystemOfUnits import *
 from AthenaCommon import Logging
 from time import time
 import os, os.path, string, sys
-import cppyy
+import ROOT,cppyy
 
 # TODO: Rename to AppProfiler, to avoid class/variable confusion
 class _app_profiler(object):
@@ -113,8 +113,7 @@ class G4AtlasEngine:
         # pylcgdict default dictionaries
         self.load_Dict('AtlasSealCLHEPDict')
         self.load_Dict('G4AtlasControlDict')
-        G4AtlasEngine.gbl = cppyy.makeNamespace("")
-        G4AtlasEngine._ctrl = G4AtlasEngine.gbl.SimControl()
+        G4AtlasEngine._ctrl = ROOT.SimControl()
         self.init_status = 0
 
         self.useISF = useISF