diff --git a/cmake/modules/AddCephTest.cmake b/cmake/modules/AddCephTest.cmake
index cf0509f7153..ab59c45d9b0 100644
--- a/cmake/modules/AddCephTest.cmake
+++ b/cmake/modules/AddCephTest.cmake
@@ -13,7 +13,8 @@ function(add_ceph_test test_name test_path)
     CEPH_BUILD_DIR=${CMAKE_BINARY_DIR}
     LD_LIBRARY_PATH=${CMAKE_BINARY_DIR}/lib
     PATH=${CMAKE_RUNTIME_OUTPUT_DIRECTORY}:${CMAKE_SOURCE_DIR}/src:$ENV{PATH}
-    PYTHONPATH=${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/cython_modules/lib.linux-x86_64-2.7:${CMAKE_SOURCE_DIR}/src/pybind)
+    PYTHONPATH=${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/cython_modules/lib.linux-x86_64-2.7:${CMAKE_SOURCE_DIR}/src/pybind
+    CEPH_BUILD_VIRTUALENV=${CEPH_BUILD_VIRTUALENV})
 endfunction()
 
 #sets uniform compiler flags and link libraries