--- workdir/solenv/inc/extension_post.mk.orig	2011-02-20 18:27:20.296125000 +0900
+++ workdir/solenv/inc/extension_post.mk.orig	2011-03-02 22:11:14.669625000 +0900
@@ -78,7 +78,9 @@ 
 
 .IF "$(PACK_RUNTIME)"!=""
 PACK_RUNTIME_FLAG:=$(MISC)/$(TARGET)_pack_runtime.flag
+.IF "$(EXTENSION_TARGET)"!=""
 $(EXTENSION_TARGET) : $(PACK_RUNTIME_FLAG)
+.ENDIF          # "$(EXTENSION_TARGET)"!=""
 
 $(EXTENSIONDIR) :
 	@@-$(MKDIRHIER) $(@:d)