Bug#465708: An error is made in postinst

[Jonny]

Package: grub-pc
Version: 1.96+20080213-1
Severity: important

A post-installation script can vomit an error and cannot install it.

The output of -x:
 Setting up grub-pc (1.96+20080213-1) ...
 + case "$1" in
 + . /usr/share/debconf/confmodule
 ++ '[' '!' '' ']'
 ++ PERL_DL_NONLAZY=1
 ++ export PERL_DL_NONLAZY
 ++ '[' '' ']'
 ++ exec /usr/share/debconf/frontend /var/lib/dpkg/info/grub-pc.postinst configure 1.96+20080210-1
 + case "$1" in
 + . /usr/share/debconf/confmodule
 ++ '[' '!' 1 ']'
 ++ '[' -z '' ']'
 ++ exec
 ++ '[' '' ']'
 ++ exec
 ++ DEBCONF_REDIR=1
 ++ export DEBCONF_REDIR
 + test -e /boot/grub/device.map
 + test -e /boot/grub/core.img
 + db_get grub-pc/linux_cmdline
 + _db_cmd 'GET grub-pc/linux_cmdline'
 + IFS=' '
 + printf '%s\n' 'GET grub-pc/linux_cmdline'
 + IFS='
 '
 + read -r _db_internal_line
 + RET=fillme
 + case ${_db_internal_line%%[   ]*} in
 + return 0
 + '[' fillme == fillme ']'
 + echo 'Internal error in grub-pc package.  Please file a bug report.'
 Internal error in grub-pc package.  Please file a bug report.
 + exit 1
 dpkg: error processing grub-pc (--configure):
  subprocess post-installation script returned error exit status 1