diff --git a/proton-c/src/tests/CMakeLists.txt b/proton-c/src/tests/CMakeLists.txt
index e8b702abed..0bd734bb85 100644
--- a/proton-c/src/tests/CMakeLists.txt
+++ b/proton-c/src/tests/CMakeLists.txt
@@ -65,12 +65,13 @@ if(HAS_PROACTOR)
   if(WIN32)
     # set(path "$<TARGET_FILE_DIR:proactor-broker>;$<TARGET_FILE_DIR:qpid-proton>")
   else(WIN32)
-    set(path "${CMAKE_RUNTIME_OUTPUT_DIRECTORY}:$ENV{PATH}")
+    set(test_path "${CMAKE_CURRENT_BINARY_DIR}:$<TARGET_FILE_DIR:proactor-broker>:${CMAKE_RUNTIME_OUTPUT_DIRECTORY}:$ENV{PATH}")
   endif(WIN32)
   # Add the tools directory for the 'proctest' module
   set_search_path(pypath "${CMAKE_SOURCE_DIR}/tools/py" "$ENV{PYTHON_PATH}")
 
-  add_test(NAME c-fdlimit-tests COMMAND ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/fdlimit.py)
+  set(run_env ${PYTHON_EXECUTABLE} ${CMAKE_SOURCE_DIR}/proton-c/env.py "PATH=${test_path}" "PYTHONPATH=${pypath}")
+  add_test(NAME c-fdlimit-tests COMMAND ${run_env} -- ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/fdlimit.py)
       #WORKING_DIRECTORY ${CMAKE_RUNTIME_OUTPUT_DIRECTORY})
-  set_tests_properties(c-fdlimit-tests PROPERTIES ENVIRONMENT "PATH=${path};PYTHONPATH=${pypath}")
+  set_tests_properties(c-fdlimit-tests PROPERTIES ENVIRONMENT "PATH=${test_path};PYTHONPATH=${pypath}")
 endif(HAS_PROACTOR)