bug#4739: 23.1.50; recursive delete fails

In the following situation Emacs signals an error:

$ mkdir -p /tmp/test
$ ln -s /tmp /tmp/test
$ emacs -Q /tmp

Now move point to the 'test' directory, type 'D' and confirm that you
want to delete the directory recursively.  An error message appears in
the echo area:
(file-error Removing directory Not a directory /tmp/test/tmp)


In GNU Emacs 23.1.50.1 (i486-pc-linux-gnu, GTK+ Version 2.18.2)
 of 2009-10-13 on turtle
(Sorry for not checking a newer version -- Savannah appears to be down,
 so I cannot upgrade ATM.)

Windowing system distributor `The X.Org Foundation', version 11.0.10605000
configured using `configure  '--build=i486-linux-gnu' 'build_alias=i486-linux-gnu' 'CFLAGS=-DGTK_DISABLE_DEPRECATED -g -O2''


Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: C
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: C
  value of $XMODIFIERS: nil
  locale-coding-system: nil
  default enable-multibyte-characters: t

Major mode: Group

Minor modes in effect:
  gnus-undo-mode: t
  display-time-mode: t
  auto-image-file-mode: t
  show-paren-mode: t
  tooltip-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  global-auto-composition-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  temp-buffer-resize-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
C-x d / t m <tab> <return> M-x t o g g l e - d e b 
<tab> e r r <tab> <return> <down> <down> <down> <down> 
<down> <down> <down> <down> <down> D y e s <return> 
<up> <return> C-h e M-x <up> <return> C-x 1 M-x e m 
a c s - v e s <backspace> r s i <tab> <return> M-x 
C-g C-x d ~ <return> M-x g n u s <return> C-g M-x <up> 
<return> <down> <down> <down> <down> <down> <down> 
<down> <down> <down> <down> <down> <down> <down> <down> 
<down> <down> <down> SPC q M-x r e p o e <backspace> 
r t - e m <tab> <return>

Recent messages:
Checking new news...
Opening nnfolder server on archive...done
Opening nntp server on news.gnus.org...done
Opening nntp server on news.eternal-september.org...done
Checking new news...done
Retrieving newsgroup: gmane.emacs.devel...
Opening nntp server on news.gmane.org...done
Fetching headers for gmane.emacs.devel...done
Scoring...done
Generating summary...done

Load-path shadows:
None found.

Features:
(shadow ispell emacsbug sort gnus-cite smiley ansi-color mail-extr
gnus-async gnus-bcklg gnus-ml disp-table parse-time timezone byte-opt
bytecomp byte-compile nnfolder nndraft nnmh vc-git auth-source
gnus-agent gnus-srvr gnus-score score-mode nnvirtual gnus-msg gnus-art
mm-uu mml2015 epg-config mm-view smime dig nntp gnus-cache gnus-sum nnoo
gnus-group gnus-undo nnmail mail-source format-spec gnus-start gnus-spec
gnus-int gnus-range message sendmail ecomplete rfc822 mml mml-sec
password-cache mm-decode mm-bodies mm-encode mailcap mail-parse rfc2231
rfc2047 rfc2045 qp ietf-drums mailabbrev gmm-utils mailheader canlock
sha1 hex-util hashcash gnus-win gnus gnus-ems nnheader gnus-util netrc
time-date mail-utils mm-util mail-prsvr wid-edit cus-start cus-load
dired-x dired-aux dired time server uniquify advice help-fns help-mode
easymenu view advice-preload po generic-x regexp-opt image-file paren
add-ons tooltip ediff-hook vc-hooks lisp-float-type mwheel x-win x-dnd
tool-bar dnd fontset image fringe lisp-mode register page menu-bar
rfn-eshadow timer select scroll-bar mldrag mouse jit-lock font-lock
syntax facemenu font-core frame cham georgian utf-8-lang misc-lang
vietnamese tibetan thai tai-viet lao korean japanese hebrew greek
romanian slovak czech european ethiopic indian cyrillic chinese
case-table epa-hook jka-cmpr-hook help simple abbrev loaddefs button
minibuffer faces cus-face text-properties overlay md5 base64 format env
code-pages mule custom widget hashtable-print-readable backquote
make-network-process dbusbind gtk x-toolkit x multi-tty emacs)