[Plugin: W3 Total Cache] Errors when activating APC

A few weeks ago I have upgraded to WordPress multisite to use the new features and maybe get some people to write on other sections of my blog. Slowly I am trying to get things running as previously and the last thing on my list is W3TC, which runs atm on disk caching. To speed things up I reactivated apc on the machine and when i enable APC I start to get errors.

/etc/php.d/apc.ini

extension = apc.so
apc.enabled = 1
apc.shm_size = 256M
apc.include_once_override = 1
apc.mmap_file_mask = /tmp/apc.XXXXXX
apc.shm_segments = 1
apc.ttl = 3600
apc.user_ttl = 3600
Selective caching

upon calling apc.php I can see that it is running properly

General Cache Information
APC Version	3.1.9
PHP Version	5.3.8

But then the Admin Backend shows this error:

It appears Page Cache URL rewriting is not working. If using apache, verify that the server configuration allows .htaccess or if using nginx verify all configuration files are included in the configuration.
It appears Minify URL rewriting is not working. If using apache, verify that the server configuration allows .htaccess or if using nginx verify all configuration files are included in the configuration.

and the apache log shows this error:

mmo-game.eu/statistics/logs/error_log <==
[Sun Sep 18 16:49:33 2011] [error] [client 189.15.46.63] PHP Fatal error:  require() [<a href='function.require'>function.require</a>]: Cannot redeclare class minify_css_compressor in mmo-game.eu/httpdocs/wp-content/plugins/w3-total-cache/lib/Minify/Minify/CSS.php on line 52, referer: https://www.myrddin.de/
[Sun Sep 18 16:49:33 2011] [error] [client 189.15.46.63] PHP Fatal error:  require() [<a href='function.require'>function.require</a>]: Cannot redeclare class minify_css_compressor in mmo-game.eu/httpdocs/wp-content/plugins/w3-total-cache/lib/Minify/Minify/CSS.php on line 52, referer: https://www.myrddin.de/

Any idea how to solve this?

Thanks