[horde] Upgrading from 1.x to horde 4

[Paul Ronald]

Hello,

i am upgrading my horde to 4, but when i have to execute the
webmail-install, i get this error:

//--------------------------------------
Warning: include_once(Log.php): failed to open stream: No such file or
directory in /var/www/html/horde/lib/Horde.php on line 14

Warning: include_once(): Failed opening 'Log.php' for inclusion
(include_path='/var/www/html/horde/lib:.:/usr/share/pear:/usr/share/php')
in /var/www/html/horde/lib/Horde.php on line 14

Warning: set_error_handler() expects the argument (Horde::errorHandler) to
be a valid callback in /var/www/html/horde/lib/core.php on line 57

Installing Horde Groupware Webmail Edition

Fatal error: Class 'Horde_Registry' not found in
/usr/share/pear/Horde/Core/Bundle.php on line 60
//--------------------------------------

i have read this "http://www.horde.org/apps/webmail/docs/INSTALL"

I think that the problem can be in the include_path og /etc/php.ini.

Thank you