/etc/release contents broken

[Thomas Klausner <wiz%NetBSD.org@localhost>]

Sometime between 20131023 and 20131031, /etc/release was broken.
Nearly all values are recorded as "(undefined)". It now looks like
this for me (with the same build command line as before):

NetBSD 6.99.25/amd64

Copyright (c) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
    2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013
    The NetBSD Foundation, Inc.  All rights reserved.
Copyright (c) 1982, 1986, 1989, 1991, 1993
    The Regents of the University of California.  All rights reserved.

Build settings:
          Build date   Thu Oct 31 17:35:29 UTC 2013
            Built by   wiz%yt.nih.at@localhost

           BSDOBJDIR = (undefined)
           BSDSRCDIR = (undefined)
             BUILDID = (undefined)
             DESTDIR = '/archive/build/amd64.clang.20131031'
          DISTRIBVER = (undefined)
  EXTERNAL_TOOLCHAIN = (undefined)
            HAVE_GCC = (undefined)
            HAVE_GDB = (undefined)
           HAVE_LLVM = 'yes'
            HAVE_PCC = (undefined)
     INSTALLWORLDDIR = (undefined)
         KERNARCHDIR = (undefined)
         KERNCONFDIR = (undefined)
          KERNOBJDIR = (undefined)
          KERNSRCDIR = (undefined)
             MACHINE = 'amd64'
        MACHINE_ARCH = 'x86_64'
                MAKE = '/archive/build/tools.clang/bin/nbmake'
            MAKECONF = (undefined)
           MAKEFLAGS = ' -d e -m /archive/foreign/src/share/mk -j 4 -J 15,16 
.MAKE.LEVEL.ENV=MAKELEVEL HOST_OSTYPE=NetBSD-6.99.24-amd64 MKOBJDIRS=yes 
NOPOSTINSTALL=1 USETOOLS=yes _SRC_TOP_=/archive/foreign/src 
_SRC_TOP_OBJ_=/usr/obj/src.amd64 _THISDIR_=etc/'
          MAKEOBJDIR = '/disk/3/archive/obj/src.amd64/etc'
    MAKEOBJDIRPREFIX = (undefined)
         MAKEVERBOSE = (undefined)
               MKATF = (undefined)
               MKBFD = (undefined)
          MKBINUTILS = (undefined)
          MKCATPAGES = (undefined)
            MKCRYPTO = (undefined)
        MKCRYPTO_RC5 = (undefined)
               MKCVS = (undefined)
             MKDEBUG = (undefined)
          MKDEBUGLIB = (undefined)
               MKDOC = (undefined)
            MKDTRACE = (undefined)
       MKDYNAMICROOT = (undefined)
               MKGCC = (undefined)
           MKGCCCMDS = (undefined)
               MKGDB = (undefined)
            MKHESIOD = (undefined)
              MKHTML = (undefined)
            MKIEEEFP = (undefined)
             MKINET6 = (undefined)
              MKINFO = (undefined)
          MKIPFILTER = (undefined)
          MKKERBEROS = (undefined)
              MKKYUA = (undefined)
              MKLDAP = (undefined)
           MKLINKLIB = (undefined)
              MKLINT = (undefined)
              MKLLVM = 'yes'
               MKMAN = (undefined)
              MKMANZ = (undefined)
              MKMDNS = (undefined)
               MKNLS = (undefined)
               MKNPF = (undefined)
               MKOBJ = (undefined)
           MKOBJDIRS = 'yes'
               MKPAM = (undefined)
               MKPCC = (undefined)
                MKPF = (undefined)
               MKPIC = (undefined)
        MKPICINSTALL = (undefined)
            MKPICLIB = (undefined)
           MKPOSTFIX = (undefined)
           MKPROFILE = (undefined)
             MKSHARE = (undefined)
              MKSKEY = (undefined)
         MKSOFTFLOAT = (undefined)
         MKSTATICLIB = (undefined)
          MKUNPRIVED = (undefined)
            MKUPDATE = (undefined)
               MKX11 = 'yes'
                MKYP = (undefined)
          NBUILDJOBS = (undefined)
        NETBSDSRCDIR = '/archive/foreign/src'
          NOCLEANDIR = (undefined)
       NODISTRIBDIRS = (undefined)
          NOINCLUDES = (undefined)
          OBJMACHINE = (undefined)
          RELEASEDIR = '/usr/obj/src.amd64/releasedir'
   RELEASEMACHINEDIR = (undefined)
   TOOLCHAIN_MISSING = (undefined)
             TOOLDIR = '/archive/build/tools.clang'
          USE_HESIOD = (undefined)
           USE_INET6 = (undefined)
        USE_JEMALLOC = (undefined)
        USE_KERBEROS = (undefined)
            USE_LDAP = (undefined)
             USE_PAM = (undefined)
            USE_SKEY = (undefined)
              USE_YP = (undefined)
            USETOOLS = 'yes'
      USR_OBJMACHINE = (undefined)
           X11SRCDIR = (undefined)
          X11FLAVOUR = (undefined)

 Thomas