[horde] Error messages in logs

[Nicolas Fo]

Hello,

I've those lines in Horde logs I can't resolve :

2012-09-20T14:17:59+02:00 ERR: HORDE [horde] User is not authorized for 
imp [pid 18755 on line 1305 of "/usr/share/php/Horde/Registry.php"]
2012-09-20T14:17:59+02:00 ERR: HORDE [horde] User is not authorized for 
gollem [pid 18755 on line 1305 of "/usr/share/php/Horde/Registry.php"]
2012-09-20T14:19:03+02:00 ERR: HORDE You must configure a Horde_Image 
driver to use Ansel [pid 18757 on line 46 of 
"/var/www/horde/ansel/lib/Application.php"]

I've those errors when I'm using Administrator user (when all users are 
redirected to Administrator). it's the same problem using another user 
using htaccess authentication.

Horde_image driver : Google doesn't what it is, and i don't know where 
it must be configured in the admin panel..

Any idea ?

Thnks a lot

Nicolas