diff --git a/overviewer.py b/overviewer.py
index 3f618ed..9a5856b 100755
--- a/overviewer.py
+++ b/overviewer.py
@@ -468,6 +468,8 @@ dir but you forgot to put quotes around the directory, since it contains spaces.
 
     # create the distributed render
     r = rendernode.RenderNode(q, options)
+    # for the pool_initializer
+    r.builtin_custom_rendermodes = builtin_custom_rendermodes
     
     # write out the map and web assets
     m = googlemap.MapGen(q, configInfo=options)
diff --git a/overviewer_core/rendernode.py b/overviewer_core/rendernode.py
index 4d2fc5d..18cc278 100644
--- a/overviewer_core/rendernode.py
+++ b/overviewer_core/rendernode.py
@@ -63,6 +63,8 @@ def pool_initializer(rendernode):
     c_overviewer.init_chunk_render()
     
     # setup c_overviewer rendermode customs / options
+    for mode in rendernode.builtin_custom_rendermodes:
+        c_overviewer.add_custom_render_mode(mode, rendernode.builtin_custom_rendermodes[mode])
     for mode in rendernode.options.custom_rendermodes:
         c_overviewer.add_custom_render_mode(mode, rendernode.options.custom_rendermodes[mode])
     for mode in rendernode.options.rendermode_options: