bug#5255: 23.1.90; Wrong prompt in term

[Fabian Ezequiel Gallina]

In emacs 23.1 when I use M-x term the prompt is rendered correctly to
whatever is defined on the PS1 environment variable. But in 23.1.90.1 it
prompts whatever is defined in the PS1 but also before that, it prompts
0;<user>@<host>:<location>.

The steps to reproduce it are quite simple:

emacs -Q
M-x term

The prompt is rendered like this:

0;fgallina@cuca:~/Builds/emacs[fgallina@cuca emacs]$

Since my PS1 is set to

PS1='[\u@\h \W]\$ '

the expected result is:

[fgallina@cuca emacs]$

In GNU Emacs 23.1.90.1 (x86_64-unknown-linux-gnu, GTK+ Version 2.18.5)
 of 2009-12-20 on cuca
Windowing system distributor `The X.Org Foundation', version 11.0.10703901
Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  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: es_AR.UTF-8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: Fundamental

Minor modes in effect:
  tooltip-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  blink-cursor-mode: t
  global-auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo>
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo>
<help-echo> <help-echo> <help-echo> M-x t e r m <return>
<return> l s <return> M-c <backspace> M-x <backspace>
C-c b <return> M-x r e m p o <backspace> <backspace>
<backspace> p o <tab> r <tab> <return>

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
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