Authentification error bug wth imp

[Chojin]

Hello,

I installed lastest Horde and Imp versions.
I configured imp to use pop3 mail server (and not an imap server).

When I go to my imp web site, I type the correct username/pass and
everything works.
But, if I put an incorrect username/password, imp says:

Warning: Constant deny_login already defined in
/var/www/tarakan-network.com/horde/lib/horde.lib on line 13
Warning: Constant no_action already defined in
/var/www/tarakan-network.com/horde/lib/horde.lib on line 18
Warning: Constant horde_login already defined in
/var/www/tarakan-network.com/horde/lib/horde.lib on line 19
Warning: Constant mailto already defined in
/var/www/tarakan-network.com/horde/lib/horde.lib on line 20
Warning: Constant horde_signup already defined in
/var/www/tarakan-network.com/horde/lib/horde.lib on line 21
...

I click on stop button on my browser to stop these warnings.

When I want to go again to my imp web site, my browser tries to load it
but
he never can...
Apache launchs lots of httpd programs to answer to my request...
I need to restart apache in order to have my imp web site okay again.

Someone has got an idea ?
I am on FreeBSD 4.3 Stable.
I use IMP 2.2.6 and Horde 1.2.6 and PHP 4.0.6 (I checked
http://www.horde.org/imp/contrib/php-4.0.4pl1-imap-patch.txt
but everything are already added in PHP 4.0.6)

Regards.

Chojin