diff --git a/cpp/BoostParts/CMakeLists.txt b/cpp/BoostParts/CMakeLists.txt
index 4ced7d8f..51dd1f82 100644
--- a/cpp/BoostParts/CMakeLists.txt
+++ b/cpp/BoostParts/CMakeLists.txt
@@ -31,7 +31,8 @@ cmake_minimum_required( VERSION 2.8 )
 
 project( BoostParts )
 
-find_package( PythonLibs REQUIRED )
+set( Python_ADDITIONAL_VERSIONS 2.7 2.6 2.5 )
+find_package( PythonLibs 2 REQUIRED )
 
 file( GLOB_RECURSE SOURCES *.cpp )
 
diff --git a/cpp/ycm/CMakeLists.txt b/cpp/ycm/CMakeLists.txt
index 429fd5d4..b2514f8c 100644
--- a/cpp/ycm/CMakeLists.txt
+++ b/cpp/ycm/CMakeLists.txt
@@ -19,6 +19,7 @@ cmake_minimum_required( VERSION 2.8 )
 
 project( ycm_core )
 
+set( Python_ADDITIONAL_VERSIONS 2.7 2.6 2.5 )
 find_package( PythonLibs 2 REQUIRED )
 
 option( USE_CLANG_COMPLETER "Use Clang semantic completer for C/C++/ObjC" OFF )