There's scattered precedence on Stack Overflow to translate questions asked in one language, while leaving the original in-tact.
Oinch Fe duble We jay mi lay dingleberry?
This is the translated version of the question, originally asked in TimPostuguese
You won't see it often, and it's done more as a utility for folks to spot problems with the translation itself than anything. It's also only done when others have run the post through Google translate (or just read it, knowing the language) then contributed valuable answers that received votes. Thus, it became a question and a state of a question that were equally worth preserving.
The stance should be that we entertain questions only in English, without totally closing the door to a few exceptions, but they really should be exceptional. Just translating the question isn't always helpful, as the question author might .. well .. not get much help out of English answers.
Your call, really - I just wanted to point out what had been done in the past.