diff --git a/SConstruct b/SConstruct
index 7ce0e6b1f..08c403c10 100644
--- a/SConstruct
+++ b/SConstruct
@@ -1152,6 +1152,9 @@ if not preconfigured:
         if env['THREADING'] == 'multi':
             env.Append(CXXFLAGS = '-mt')
 
+    if env['SHAPE_MEMORY_MAPPED_FILE']:
+        env.Append(CPPDEFINES = '-DSHAPE_MEMORY_MAPPED_FILE')
+
     # allow for mac osx /usr/lib/libicucore.dylib compatibility
     # requires custom supplied headers since Apple does not include them
     # details: http://lists.apple.com/archives/xcode-users/2005/Jun/msg00633.html
diff --git a/src/build.py b/src/build.py
index 0dba64a0e..ce8570da2 100644
--- a/src/build.py
+++ b/src/build.py
@@ -335,10 +335,6 @@ if env['SVG_RENDERER']: # svg backend
     lib_env.Append(CPPDEFINES = '-DSVG_RENDERER')
     libmapnik_defines.append('-DSVG_RENDERER')
 
-if env['SHAPE_MEMORY_MAPPED_FILE']:
-    lib_env.Append(CPPDEFINES = '-DSHAPE_MEMORY_MAPPED_FILE')
-    libmapnik_defines.append('-DSHAPE_MEMORY_MAPPED_FILE')
-
 if env.get('BOOST_LIB_VERSION_FROM_HEADER'):
     boost_version_from_header = int(env['BOOST_LIB_VERSION_FROM_HEADER'].split('_')[1])
     if boost_version_from_header < 46: