diff -rupN comm-beta.orig/mozilla/config/baseconfig.mk comm-beta/mozilla/config/baseconfig.mk
--- comm-beta.orig/mozilla/config/baseconfig.mk	2015-04-23 17:38:36.328509738 +0200
+++ comm-beta/mozilla/config/baseconfig.mk	2015-04-23 17:39:42.753800397 +0200
@@ -2,10 +2,10 @@
 # directly in python/mozbuild/mozbuild/base.py for gmake validation.
 # We thus use INCLUDED_AUTOCONF_MK to enable/disable some parts depending
 # whether a normal build is happening or whether the check is running.
-includedir := $(includedir)/$(MOZ_APP_NAME)-$(MOZ_APP_VERSION)
-idldir = $(datadir)/idl/$(MOZ_APP_NAME)-$(MOZ_APP_VERSION)
-installdir = $(libdir)/$(MOZ_APP_NAME)-$(MOZ_APP_VERSION)
-sdkdir = $(libdir)/$(MOZ_APP_NAME)-devel-$(MOZ_APP_VERSION)
+includedir := $(includedir)/$(MOZ_APP_NAME)
+idldir = $(datadir)/idl/$(MOZ_APP_NAME)
+installdir = $(libdir)/$(MOZ_APP_NAME)
+sdkdir = $(libdir)/$(MOZ_APP_NAME)-devel
 ifndef TOP_DIST
 TOP_DIST = dist
 endif