diff --git a/scripts/poky-env-internal b/scripts/poky-env-internal
index b3e5d40903..489956ebce 100755
--- a/scripts/poky-env-internal
+++ b/scripts/poky-env-internal
@@ -79,6 +79,8 @@ export LANG=C
 # Kill PYTHONPATH as otherwise the Python specified there will conflict with
 # python-native.
 unset PYTHONPATH
+# Don't allow custom GConf schema paths to get into the system
+unset GCONF_SCHEMA_INSTALL_SOURCE
 
 echo
 echo "### Shell environment set up for Poky builds. ###"