diff -up thunderbird-7.0/comm-beta/config/autoconf.mk.in.old thunderbird-7.0/comm-beta/config/autoconf.mk.in
--- thunderbird-7.0/comm-beta/config/autoconf.mk.in.old	2011-09-05 12:24:29.000000000 +0200
+++ thunderbird-7.0/comm-beta/config/autoconf.mk.in	2011-09-12 12:21:09.304918326 +0200
@@ -65,7 +65,7 @@ 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)
 
 MOZDEPTH	= $(DEPTH)/mozilla
diff -up thunderbird-7.0/comm-beta/mozilla/config/autoconf.mk.in.old thunderbird-7.0/comm-beta/mozilla/config/autoconf.mk.in
--- thunderbird-7.0/comm-beta/mozilla/config/autoconf.mk.in.old	2011-09-05 12:38:22.000000000 +0200
+++ thunderbird-7.0/comm-beta/mozilla/config/autoconf.mk.in	2011-09-12 12:21:24.192991555 +0200
@@ -68,7 +68,7 @@ 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
diff -up thunderbird-7.0/comm-beta/mozilla/js/src/config/autoconf.mk.in.old thunderbird-7.0/comm-beta/mozilla/js/src/config/autoconf.mk.in
--- thunderbird-7.0/comm-beta/mozilla/js/src/config/autoconf.mk.in.old	2011-09-05 12:38:30.000000000 +0200
+++ thunderbird-7.0/comm-beta/mozilla/js/src/config/autoconf.mk.in	2011-09-12 12:21:37.409056596 +0200
@@ -61,7 +61,7 @@ libdir		= @libdir@
 datadir		= @datadir@
 mandir		= @mandir@
 
-installdir	= $(libdir)/$(MOZ_APP_NAME)-$(MOZ_APP_VERSION)
+installdir	= $(libdir)/$(MOZ_APP_NAME)
 sdkdir		= $(libdir)/$(MOZ_APP_NAME)-devel-$(MOZ_APP_VERSION)
 
 TOP_DIST	= @TOP_DIST@