httpd-2.0 build problem (freebsd, autoconf-2.52)

[cm...@collab.net]

The following error happens everytime I build Apache on a FreeBSD
machine:

% make distclean
% ./buildconf
% ./configure --enable-dav --enable-so --prefix=/usr/local/apache2 \
  --with-mpm=prefork --enable-maintainer-mode

   [...]
   creating os/os2/Makefile
   creating os/Makefile
   creating os/unix/Makefile
   creating server/Makefile
   creating support/Makefile
   creating srclib/pcre/Makefile
   creating test/Makefile
   config.status: creating support/apxs
   config.status: creating support/apachectl
   config.status: creating support/dbmmanage
   config.status: creating support/log_server_status
   config.status: creating support/logresolve.pl
   config.status: creating support/phf_abuse_log.cgi
   config.status: creating support/split-logfile
   config.status: creating build/rules.mk
   config.status: creating include/ap_config_auto.h
   ./config.status: 762: Syntax error: "done" unexpected (expecting ")")

Now, the relevant portion of ./config.status reads:

   for ac_file in : $CONFIG_COMMANDS; do test "x$ac_file" = x: && continue
     ac_dest=`echo "$ac_file" | sed 's,:.*,,'`
     ac_source=`echo "$ac_file" | sed 's,[^:]*:,,'`
   
     case $ac_dest in
     esac
   done

NOTE:  ./config.status is a `sh' script, which on a Linux box is
really `bash'.  So, I temporarily made '/bin/sh' on my FreeBSD box a
link to '/usr/local/bin/bash', and *poof* the problem disappeared.

NOTE 2: I think this output is something introduced in newer versions
of autoconf (I have 2.52) but I'm not altogether sure.  This is a
bummer, because Subversion requires both Apache and autoconf-2.5. :-(