I did attempt an upgrade (-Uvh ) ..
Should I uninstall php4 first?? and how do I do this !!
Hi!
PHP4 and PHP5 will not co-exist, I think it's safest to uninstall PHP4 first.
OBS!!! Make sure you've made backups for any critical data/application... 
Find out which PHP RPMS you've got install
#rpm -qa|grep php-
Uninstall PHP RPMS with (OBS!!! --nodeps option will be required since horde & co will have php dependency)
# php -e --nodeps php php-imap php-ldap php-mysql php-
extensionAfter that follow the howto and it should work fine. Good luck...