diff --git a/config/autoconf.mk.in b/config/autoconf.mk.in
--- a/config/autoconf.mk.in
+++ b/config/autoconf.mk.in
@@ -58,17 +58,17 @@ prefix = @prefix@
exec_prefix = @exec_prefix@
bindir = @bindir@
includedir = @includedir@/$(MOZ_APP_NAME)-$(MOZ_APP_VERSION)
libdir = @libdir@
datadir = @datadir@
mandir = @mandir@
idldir = $(datadir)/idl/$(MOZ_APP_NAME)-$(MOZ_APP_VERSION)
-installdir = $(libdir)/$(MOZ_APP_NAME)-$(MOZ_APP_VERSION)
+installdir = $(libdir)/$(MOZ_APP_NAME)
sdkdir = $(libdir)/$(MOZ_APP_NAME)-devel-$(MOZ_APP_VERSION)
DIST = $(DEPTH)/dist
LIBXUL_SDK = @LIBXUL_SDK@
L10NBASEDIR = @L10NBASEDIR@
LIBXUL_DIST = @LIBXUL_DIST@