[horde] Horde installations broke after PHP Upgrade

[Alejandro Lengua - Virtual Orbis]

Recently upgraded PHP and Zend Optimizer in my web server to versions 
4.3.11 and 2.5.7 respectively
and my Horde 2.x and 3.x installations became broke and showing these 
errors.

Any ideas on how to fix this?

Thanks in advance
Alejandro Lengua

*Error messages...

Notice*: Use of undefined constant SORTARRIVAL - assumed 'SORTARRIVAL' 
in */var/www/html/horde-2.2.6/imp/config/prefs.php* on line *503*

*Notice*: Use of undefined constant SORTARRIVAL - assumed 'SORTARRIVAL' 
in */var/www/html/horde-2.2.6/imp/config/prefs.php* on line *507*

*Notice*: Use of undefined constant SORTDATE - assumed 'SORTDATE' in 
*/var/www/html/horde-2.2.6/imp/config/prefs.php* on line *508*

*Notice*: Use of undefined constant SORTFROM - assumed 'SORTFROM' in 
*/var/www/html/horde-2.2.6/imp/config/prefs.php* on line *509*

*Notice*: Use of undefined constant SORTSUBJECT - assumed 'SORTSUBJECT' 
in */var/www/html/horde-2.2.6/imp/config/prefs.php* on line *510*

*Notice*: Use of undefined constant SORTSIZE - assumed 'SORTSIZE' in 
*/var/www/html/horde-2.2.6/imp/config/prefs.php* on line *511*

*Warning*: Cannot modify header information - headers already sent by 
(output started at /var/www/html/horde-2.2.6/imp/config/prefs.php:503) 
in */var/www/html/horde-2.2.6/lib/Secret.php* on line *144*

*Notice*: Use of undefined constant SORTARRIVAL - assumed 'SORTARRIVAL' 
in */var/www/html/horde-2.2.6/imp/config/prefs.php* on line *503*

*Notice*: Use of undefined constant SORTARRIVAL - assumed 'SORTARRIVAL' 
in */var/www/html/horde-2.2.6/imp/config/prefs.php* on line *507*

*Notice*: Use of undefined constant SORTDATE - assumed 'SORTDATE' in 
*/var/www/html/horde-2.2.6/imp/config/prefs.php* on line *508*

*Notice*: Use of undefined constant SORTFROM - assumed 'SORTFROM' in 
*/var/www/html/horde-2.2.6/imp/config/prefs.php* on line *509*

*Notice*: Use of undefined constant SORTSUBJECT - assumed 'SORTSUBJECT' 
in */var/www/html/horde-2.2.6/imp/config/prefs.php* on line *510*

*Notice*: Use of undefined constant SORTSIZE - assumed 'SORTSIZE' in 
*/var/www/html/horde-2.2.6/imp/config/prefs.php* on line *511*