diff -upr comm-esr31.orig/mozilla/config/baseconfig.mk comm-esr31/mozilla/config/baseconfig.mk
--- comm-esr31.orig/mozilla/config/baseconfig.mk	2014-07-22 09:44:22.000000000 +0300
+++ comm-esr31/mozilla/config/baseconfig.mk	2014-07-22 09:46:45.000000000 +0300
@@ -2,7 +2,7 @@
 # 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.
-installdir = $(libdir)/$(MOZ_APP_NAME)
+installdir = $(libdir)/$(MOZ_APP_NAME)-beta
 ifeq (.,$(DEPTH))
 DIST = dist
 else