I may be wrong, but I can suggest three methods:
1. (conceptually shouldn't work) : apt-get remove <package name>; apt-get install <package name>
2. (should work...your intentions must break your system): apt-get purge <package name>; apt-get install <package name>
3. *(recommended method): dpkg-reconfigure <package name/s>
Make sure the methods won't break your system! That's just a suggestion.
Good luck!