diff --git a/conf/layer.conf b/conf/layer.conf
index 4d900c9..6950246 100644
--- a/conf/layer.conf
+++ b/conf/layer.conf
@@ -2,10 +2,10 @@
 # Copyright 2011 Intel Corporation
 
 # We have a conf and classes directory, prepend to BBPATH to prefer our versions
-BBPATH := "${LAYERDIR}:${BBPATH}"
+BBPATH .= ":${LAYERDIR}"
 
 # We have a recipes directory, add to BBFILES
-BBFILES := "${BBFILES} ${LAYERDIR}/recipes-*/*/*.bb ${LAYERDIR}/recipes-*/*/*.bbappend"
+BBFILES += "${LAYERDIR}/recipes-*/*/*.bb ${LAYERDIR}/recipes-*/*/*.bbappend"
 
 BBFILE_COLLECTIONS += "meta-opie"
 BBFILE_PATTERN_meta-opie := "^${LAYERDIR}/"