I can't install php5-apc: ~# apt-get install php5-apc Reading package lists... Done Building dependency tree Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation: The following packages have unmet dependencies: php5-apc : Depends: php5-common (= 5.3.19-1~dotdeb.0) but 5.3.8-2 is to be installed E: Broken packages Have fresh Debian 6 and deb http://packages.dotdeb.org squeeze all deb-src http://packages.dotdeb.org squeeze all in source.list. P. S. I'm not very experienced—just trying to set up a server by the tutorial.