diff --git a/cmake_support/CopyDependencies.cmake b/cmake_support/CopyDependencies.cmake
index 704512714983e6524fa971a621adef2a281f75be..d95d79cf69d09235802d23e02a2e9b8ac631e495 100644
--- a/cmake_support/CopyDependencies.cmake
+++ b/cmake_support/CopyDependencies.cmake
@@ -423,13 +423,13 @@ function(copy_python include_path version new_binary_path)
   if(APPLE)
     file(COPY ${python_root_dir}/Resources/Python.app/Contents/MacOS/Python DESTINATION ${CMAKE_INSTALL_PREFIX}/bin)
     set(${new_binary_path} "${CMAKE_INSTALL_PREFIX}/bin/Python" PARENT_SCOPE)
-    string(REGEX REPLACE "pyexec=\"[^\n\$]*\"" "pyexec=\"\$DNG_BINDIR/Python\"" ost_config "${ost_config}")
+    string(REGEX REPLACE "pyexec=\"[^\n\$]*\"" "pyexec=\"\$DNG_BINDIR/Python\"\nexport PYTHONHOME=\$DNG_ROOT" ost_config "${ost_config}")
   else(APPLE)
     file(GLOB python_libs "${python_root_dir}/${LIB_DIR}/libpython${version}.so*")
     file(COPY ${python_libs} DESTINATION ${CMAKE_INSTALL_PREFIX}/${LIB_DIR})
     file(COPY ${python_root_dir}/bin/python${version} DESTINATION ${CMAKE_INSTALL_PREFIX}/bin)
     set(${new_binary_path} "${CMAKE_INSTALL_PREFIX}/bin/python${version}" PARENT_SCOPE)
-    string(REGEX REPLACE "pyexec=\"[^\n\$]*\"" "pyexec=\"\$DNG_BINDIR/python${version}\"" ost_config "${ost_config}")
+    string(REGEX REPLACE "pyexec=\"[^\n\$]*\"" "pyexec=\"\$DNG_BINDIR/python${version}\"\nexport PYTHONHOME=\$DNG_ROOT" ost_config "${ost_config}")
   endif(APPLE)
   write_config("${ost_config}")
 endfunction(copy_python)
@@ -837,7 +837,7 @@ endfunction(copy_qt)
 # function is_system_lib (Linux)
 #=============================================================================
 function(is_system_lib item system_var)
-  if(item MATCHES "libc\\.|libstdc\\+\\+\\.|libelf|ld-linux\\.|libexpat\\.|libgcc_s\\.|libglib\\.|/cmov/|libice\\.|libSM\\.|libX\\.|libg\\.|libGL\\.|libfontconfig\\.|libfreetype\\.|libdrm\\.|libxcb\\.|libICE\\.|libnvidia\\.|libc\\.")
+  if(item MATCHES "^/lib/|libX|pylibc\\.|libstdc\\+\\+\\.|libelf|ld-linux\\.|libexpat\\.|libgcc_s\\.|libglib\\.|/cmov/|libice\\.|libSM\\.|libX\\.|libg\\.|libGL\\.|libfontconfig\\.|libfreetype\\.|libdrm\\.|libxcb\\.|libICE\\.|libnvidia\\.|libc\\.")
     set(${system_var} 1 PARENT_SCOPE)
   else()
     set(${system_var}  0 PARENT_SCOPE)