diff --git a/DDG4/CMakeLists.txt b/DDG4/CMakeLists.txt
index 6e8f05e093cf98b6f6128b6922f189da258bda44..f87bb024f8cfe87d7b3435d776a480edbb276807 100644
--- a/DDG4/CMakeLists.txt
+++ b/DDG4/CMakeLists.txt
@@ -122,7 +122,7 @@ target_link_libraries(g4FromXML DDG4)
 file(GLOB DDG4_python python/*.py python/*.C)
 install(FILES ${DDG4_python} DESTINATION lib/python${Python_VERSION_MAJOR}.${Python_VERSION_MINOR}/site-packages)
 
-install(PROGRAMS python/DDSim/bin/ddsim DESTINATION bin)
+install(PROGRAMS python/DDSim/bin/ddsim.py DESTINATION bin RENAME ddsim)
 
 install(PROGRAMS python/bin/checkOverlaps.py DESTINATION bin RENAME checkOverlaps)
 install(PROGRAMS python/bin/checkGeometry.py DESTINATION bin RENAME checkGeometry)
diff --git a/DDG4/python/DDSim/bin/ddsim b/DDG4/python/DDSim/bin/ddsim.py
similarity index 100%
rename from DDG4/python/DDSim/bin/ddsim
rename to DDG4/python/DDSim/bin/ddsim.py