diff --git a/config/autoconf.mk.in b/config/autoconf.mk.in
index bea1ca3..2de10c0 100644
--- a/config/autoconf.mk.in
+++ b/config/autoconf.mk.in
@@ -61,11 +61,11 @@ MOZ_PKG_SPECIAL = @MOZ_PKG_SPECIAL@
 prefix		= @prefix@
 exec_prefix	= @exec_prefix@
 bindir		= @bindir@
-includedir	= @includedir@/$(MOZ_APP_NAME)-$(MOZ_APP_VERSION)
+includedir	= @includedir@/$(MOZ_APP_NAME)
 libdir		= @libdir@
 datadir		= @datadir@
 mandir		= @mandir@
-idldir		= $(datadir)/idl/$(MOZ_APP_NAME)-$(MOZ_APP_VERSION)
+idldir		= $(datadir)/idl/$(MOZ_APP_NAME)
 
 installdir	= $(libdir)/$(MOZ_APP_NAME)-$(MOZ_APP_VERSION)
 sdkdir		= $(libdir)/$(MOZ_APP_NAME)-devel-$(MOZ_APP_VERSION)