“Currently, the JS SDK is returning /* Not a valid locale. */. We are working on a fix now. We will update the live status as we have more information. You can following along in https://developers.facebook.com/bugs/20327564310313″Very soon this problem reported, Facebook has updated that
"The issues with JS SDK should now be resolved. "
Its sure that this issue had effected thousands of websites and blogs since 90% them have a Facebook fan page or a like button is attached with post.. This bug has been fixed by Facebook now and you can now start commenting and liking your favourit websites . . . .