diff --git a/config/RULES_DIRS b/config/RULES_DIRS
index 6808c9ef6..5db4f8d6f 100644
--- a/config/RULES_DIRS
+++ b/config/RULES_DIRS
@@ -3,8 +3,8 @@
 #
  
 
-ARCHS= $(BUILD_ARCHS) host cross
-ACTIONS = clean inc install depends
+ARCHS += $(BUILD_ARCHS) host cross
+ACTIONS += clean inc install depends
  
 dirPart = $(word 1, $(subst $(DIVIDER), ,$@))
 actionArchPart = $(subst $(dirPart)$(DIVIDER), ,$@)