This hack allows to create post models (or templates), usable in posts or private messages. In ACP, a module is added to create, edit or delete your post models.
It adds three new permissions: the first to use the post models in a specific forum, the second to use the post models in private messaging and the third to manage the post models in the ACP.
You can create for each language installed a different model. An authorized user will have the choice in his post/PM to display the models of each language.