Changes have been made in Git (develop):

commit c4115af8c6e09caa73180ad4dc6a4828929ddf85
Author: Jan Schneider <jan@horde.org>
Date:   Thu Sep 27 11:57:33 2012 +0200

     [jan] Fix sending and reading files in SSH2 driver if vfsroot is 
not set (Bug #11451).

  framework/Vfs/lib/Horde/Vfs/Ssh2.php |    6 +++++-
  framework/Vfs/package.xml            |    4 ++--
  2 files changed, 7 insertions(+), 3 deletions(-)

http://git.horde.org/horde-git/-/commit/c4115af8c6e09caa73180ad4dc6a4828929ddf85

Implemented and working.  Thank you jan.

Changes have been made in Git (master):

commit c4115af8c6e09caa73180ad4dc6a4828929ddf85
Author: Jan Schneider <jan@horde.org>
Date:   Thu Sep 27 11:57:33 2012 +0200

     [jan] Fix sending and reading files in SSH2 driver if vfsroot is 
not set (Bug #11451).

  framework/Vfs/lib/Horde/Vfs/Ssh2.php |    6 +++++-
  framework/Vfs/package.xml            |    4 ++--
  2 files changed, 7 insertions(+), 3 deletions(-)

http://git.horde.org/horde-git/-/commit/c4115af8c6e09caa73180ad4dc6a4828929ddf85

I upgraded my Ingo the other day, and I can no longer write rules for 
filtering.  I am getting this error when I try to do so:

There was an error activating the script. The driver said: Unable to 
write VFS file ".procmailrc".

I figured that this was probably because the upgrade brought in new 
files that stomped on my old config files.  But I have done a diff on 
my backends.php, backends.local.php, conf.php and prefs.php (I have no 
prefs.local.php) -- And nothing has changed.

As you can guess, I have ingo set to use procmail.  All my horde apps 
are up to date as of today.  Ssh appears to be working normally on the 
server box.  $conf[storage] is SQL and $conf[storage] is Horde 
defaults.  Horde is configured so that $conf[vfs][type]=Files on the 
local system, and $conf[vfs]=/tmp.

I thank you for your help.

-Chris

My backends.local.php:

/* Procmail Example */
$backends['procmail'] = array(
     'disabled' => false,
     'transport' => 'vfs',
     'hordeauth' => true,
     'params' => array(
         'hostspec' => 'localhost',
         'filename' => '.procmailrc',
          'vfstype' => 'ssh2',
          'port' => 22,
     ),
     'script' => 'procmail',
     'scriptparams' => array(
         'path_style' => 'maildir',
         'variables' => array(
         )
     ),
     'shares' => false
);

My backends.local.php is unaltered:
$prefGroups['script'] = array(
     'column' => _("Other Preferences"),
     'label' => _("Script Updating"),
     'desc' => _("Preferences about script updating."),
     'members' => array('auto_update'));
$_prefs['auto_update'] = array(
     'value' => 1,
     'locked' => false,
     'type' => 'checkbox',
     'desc' => _("Automatically activate the script after each change?")
);
$_prefs['show_filter_msg'] = array(
     'value' => 1,
     'locked' => false,
     'type' => 'implicit'
);
$_prefs['filter_seen'] = array(
     'value' => 0,
     'locked' => false,
     'type' => 'implicit'
);
$_prefs['rules'] = array(
     'value' => 
'a:5:{i:0;a:2:{s:4:"name";s:9:"Whitelist";s:6:"action";i:' . 
Ingo_Storage::ACTION_WHITELIST . 
';}i:1;a:3:{s:4:"name";s:8:"Vacation";s:6:"action";i:' . 
Ingo_Storage::ACTION_VACATION . 
';s:7:"disable";b:1;}i:2;a:2:{s:4:"name";s:9:"Blacklist";s:6:"action";i:' . 
Ingo_Storage::ACTION_BLACKLIST . ';}i:3;a:3:{s:4:"name";s:11:"Spam 
Filter";s:6:"action";i:' . Ingo_Storage::ACTION_SPAM . 
';s:7:"disable";b:1;}i:4;a:2:{s:4:"name";s:7:"Forward";s:6:"action";i:' . 
Ingo_Storage::ACTION_FORWARD . ';}}',
     'locked' => false,
     'type' => 'implicit'
);
$_prefs['blacklist'] = array(
     'value' => 'a:2:{s:1:"a";a:0:{}s:1:"f";s:0:"";}',
     'locked' => false,
     'type' => 'implicit'
);
$_prefs['whitelist'] = array(
     'value' => 'a:0:{}',
     'locked' => false,
     'type' => 'implicit'
);
$_prefs['vacation'] = array(
     'value' => 
'a:8:{s:9:"addresses";a:0:{}s:4:"days";i:7;s:8:"excludes";a:0:{}s:10:"ignorelist";b:1;s:6:"reason";s:0:"";s:7:"subject";s:0:"";s:5:"start";i:0;s:3:"end";i:0;}',
     'locked' => false,
     'type' => 'implicit'
);
$_prefs['forward'] = array(
     'value' => 'a:2:{s:1:"a";a:0:{}s:1:"k";i:0;}',
     'locked' => false,
     'type' => 'implicit'
);
$_prefs['spam'] = array(
     'value' => 'a:2:{s:6:"folder";N;s:5:"level";i:5;}',
     'locked' => false,
     'type' => 'implicit'
);

this is what I'm getting in the log file:

2012-09-20T17:59:34-04:00 NOTICE: HORDE [ingo] PHP ERROR: Undefined 
index: vfsroot [pid 4534 on line 785 of 
"/usr/share/php/Horde/Vfs/Ssh2.php"]
2012-09-20T17:59:34-04:00 NOTICE: HORDE [ingo] PHP ERROR: Undefined 
index: vfsroot [pid 4534 on line 785 of 
"/usr/share/php/Horde/Vfs/Ssh2.php"]
2012-09-20T17:59:34-04:00 NOTICE: HORDE [ingo] PHP ERROR: Undefined 
index: vfsroot [pid 4534 on line 785 of 
"/usr/share/php/Horde/Vfs/Ssh2.php"]

Another poster has posted the same issue on the ingo boards, though 
she was using mbox instead of maildir.