diff --git a/Event/PyDumper/python/Dumpers.py b/Event/PyDumper/python/Dumpers.py
index 512000ef2ab703ae29b10893ec8555d589c9c127..7e14295cae9e936986c8482a6716690231e3564e 100644
--- a/Event/PyDumper/python/Dumpers.py
+++ b/Event/PyDumper/python/Dumpers.py
@@ -40,8 +40,8 @@ etcone10 = 0
 nucone10 = 8
 
 # Without these, cling gets confused by forward declarations.
-ROOT.xAOD.TrackParticleContainer_v1
-ROOT.xAOD.Jet_v1
+getattr (ROOT.xAOD, 'TrackParticleContainer_v1', None)
+getattr (ROOT.xAOD, 'Jet_v1', None)
 
 # Work around a cling bug.
 if hasattr(ROOT,'TrackParticleTruthCollection'):