diff -up seamonkey-2.12/comm-release/mozilla/xpcom/idl-parser/Makefile.in.idl-parser-cachepath seamonkey-2.12/comm-release/mozilla/xpcom/idl-parser/Makefile.in
--- seamonkey-2.12/comm-release/mozilla/xpcom/idl-parser/Makefile.in.idl-parser-cachepath	2012-08-27 06:49:34.000000000 +0200
+++ seamonkey-2.12/comm-release/mozilla/xpcom/idl-parser/Makefile.in	2012-08-28 13:12:39.116991864 +0200
@@ -29,7 +29,7 @@ include $(topsrcdir)/config/rules.mk
 export:: $(PARSER_SRCS) $(PLY_PROGS)
 	$(PYTHON_PATH) \
 	  $(PLY_INCLUDE) \
-	  $(srcdir)/header.py --cachedir=. --regen
+	  $(srcdir)/header.py --cachedir=cache --regen
 
 check::
 	$(PYTHON_PATH) \
diff -up seamonkey-2.12/comm-release/mozilla/xpcom/typelib/xpidl/Makefile.in.idl-parser-cachepath seamonkey-2.12/comm-release/mozilla/xpcom/typelib/xpidl/Makefile.in
--- seamonkey-2.12/comm-release/mozilla/xpcom/typelib/xpidl/Makefile.in.idl-parser-cachepath	2012-08-27 06:49:34.000000000 +0200
+++ seamonkey-2.12/comm-release/mozilla/xpcom/typelib/xpidl/Makefile.in	2012-08-28 13:11:23.014580767 +0200
@@ -16,8 +16,8 @@ SDK_BINARY = \
   $(topsrcdir)/xpcom/idl-parser/xpidl.py \
   $(topsrcdir)/xpcom/idl-parser/header.py \
   $(topsrcdir)/xpcom/idl-parser/typelib.py \
-  $(DEPTH)/xpcom/idl-parser/xpidllex.py \
-  $(DEPTH)/xpcom/idl-parser/xpidlyacc.py \
+  $(DEPTH)/xpcom/idl-parser/cache/xpidllex.py \
+  $(DEPTH)/xpcom/idl-parser/cache/xpidlyacc.py \
   $(NULL)
 
 ifndef MOZ_SYSTEM_PLY