Невозможно установить libapache2-mod-php5

Когда я пытаюсь установить libapache2-mod-php5, я получаю сообщение об ошибке:

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 resolve the situation: The following packages have unmet dependencies: libapache2-mod-php5 : Depends: apache2-mpm-prefork (> 2.0.52) but it is not going to be installed or apache2-mpm-itk but it is not going to be installed E: Unable to correct problems, you have held broken packages. 

Я попробовал apt-get clean, update и upgrade, а также -f install и без изменений.

Есть ли способ исправить это, или есть простой способ вручную установить плагин php?