[horde] php error related to missing Save/Undo buttons in options screen

[D G Teed]

There is some problem associated with our horde + imp
which causes line 260 in lib/Horde/Prefs/UI.php to fail.

That line contains:

require $registry->get('templates', 'horde') . '/prefs/' .
$_prefs[$pref]['type'] . '.inc';

The error shows:

[Fri Jan 22 16:08:14 2010] [error] [client 131.x.x.x] PHP Warning:
Prefs_UI::require(/usr/local/www/horde/horde-webmail-1.2.3-blue/config/../templates/prefs/.inc)
[<a href='function.Prefs-UI-require'>function.Prefs-UI-require</a>]: failed
to open stream: No such file or directory in
/usr/local/www/horde/horde-webmail-1.2.3-blue/lib/Horde/Prefs/UI.php on line
260, referer: http://webmail.example.com/services/prefs.php?app=imp
[Fri Jan 22 16:08:14 2010] [error] [client 131.x.x.x] PHP Fatal error:
Prefs_UI::require() [<a href='function.require'>function.require</a>]:
Failed opening required
'/usr/local/www/horde/horde-webmail-1.2.3-blue/config/../templates/prefs/.inc'
(include_path='/usr/local/www/horde/horde-webmail-1.2.3-blue/lib:/usr/local/www/horde/horde-webmail-1.2.3-blue/lib/../pear')
in /usr/local/www/horde/horde-webmail-1.2.3-blue/lib/Horde/Prefs/UI.php on
line 260, referer: http://webmail.example.com/services/prefs.php?app=imp

The options screen for "Mailbox and Folder Display Options" appears, but is
missing
the Save, Undo and other usual submit buttons.

If looks like $_prefs[$pref]['type'] is coming up null.  What is it that
would set that up right?

--Donald