debian dependencies troubles.

distr debian sarge.
пытаюсь удалить exim4 из системы
#aptitude purge exim4-base
Reading Package Lists... Done
Building Dependency Tree
Reading extended state information
Initializing package states... Done
Reading task descriptions... Done
The following packages are unused and will be REMOVED:
exim4-config
The following packages will be automatically REMOVED:
at exim4-daemon-light mailx mutt mysql-server
The following packages will be REMOVED:
at exim4-base exim4-daemon-light mailx mutt mysql-server
0 packages upgraded, 0 newly installed, 7 to remove and 0 not upgraded.
Need to get 0B of archives. After unpacking 16.2MB will be freed.
Do you want to continue? [Y/n/?]

в зависимости к exim каким-то боком попал mysql-server .

как можно обьяснить aptitude , dpkg ... , что надо удалить только exim и не трогать mysql-server

подскажите плиз. в мануале по aptitude ничего не нашел.