Comment 3 for bug 534417

We can only fix this in software-center.
In language-selector, we have a python class called CheckLanguageSupport(), which takes two arguments, datadir="/usr/share/language-selector" and cache=, where cache is the already opened package cache in use.
Then, before installing the selected packges and their dependencies, software-center would need to call getMissingPackages(packages=[list of packages which are going to be installed]). This will return a list of translation or writing aids packages, which have not been installed yet, but where the base application is marked for installation or is already installed on the system.
Finally, software-center should depend on language-selector-common.