I'm happy to say that recently our organization (UAB) get some money to translate OJS to Catalan (and/or Spanish) so we expect to contribute to the community.
Another university (UOC, Open University of Catalonia) will release very soon a brand new Catalan translation for OJS 2.2.2 so we talked with them about how to extend their wonderful work. After our conversations, we arrive to the conclusion that our contribution could start with the "Reading tools" but we noticed this part of OJS is not multilingual.
In other words, a OJS patch need to be developed to make this part language-dependent so we happily assume this work.
The point is, as you expect, that we like to keep this translation functional between OJS versions, so we like to know if there are any rules (coding style, patching, recommendations...) about how to contribute code to OJS if we aim it to be included in core.
Let me know if I'm wrong and this patch was developed by somebody or this feature is going to be included in next OJS release.
BTW, if this work is not planned or done, any indication about where to start or how to design it, are really welcome.
Thanks a lot for your help,