We already do this with our support site where we have forums (using VBulletin). We use google translate and the results are much better than you seem to think. It works every bit as well as having a Russian user try to respond in English if their English is not so good.
If Q2A provides a way to intercept incoming requests and/or posts so they can be tagged, say with the user's locale or the locale info is already available, I am half way there. I just need to be able to plug into the input/output and if need be, first transform the data via google translate, replace the data in the stream and send it on its way.