With /sudo::/etc instead of /etc, files are not conf mode by default

[trentbuck]

The file /etc/default/tftpd-hpa uses conf mode by default, presumably
due to auto-mode-alist.  However, opening the same file with TRAMP's
sudo method: /sudo::/etc/default/tftpd-hpa, causes it to be in
fundamental mode.  Presumably this is because the auto-mode-alist
entry uses ^/ to match the root directory or similar.

In GNU Emacs 22.1.1 (x86_64-pc-linux-gnu, X toolkit, Xaw3d scroll bars)
 of 2007-07-07 on nautilus, modified by Debian
configured using `configure  '--build=x86_64-linux-gnu' 
'--host=x86_64-linux-gnu' '--prefix=/usr' '--sharedstatedir=/var/lib' 
'--libexecdir=/usr/lib' '--localstatedir=/var/lib' '--infodir=/usr/share/info' 
'--mandir=/usr/share/man' '--with-pop=yes' 
'--enable-locallisppath=/etc/emacs22:/etc/emacs:/usr/local/share/emacs/22.1/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/22.1/site-lisp:/usr/share/emacs/site-lisp:/usr/share/emacs/22.1/leim'
 '--with-x=yes' '--with-x-toolkit=athena' '--with-toolkit-scroll-bars' 
'build_alias=x86_64-linux-gnu' 'host_alias=x86_64-linux-gnu' 'CFLAGS=-DDEBIAN 
-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: en_AU.utf8
  locale-coding-system: utf-8
  default-enable-multibyte-characters: t

Major mode: Fundamental

Minor modes in effect:
  xterm-mouse-mode: t
  savehist-mode: t
  shell-dirtrack-mode: t
  icomplete-mode: t
  partial-completion-mode: t
  show-paren-mode: t
  delete-selection-mode: t
  encoded-kbd-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  unify-8859-on-encoding-mode: t
  utf-translate-cjk-mode: t
  auto-compression-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
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