For residential? That's kinda crazy... the corridor cannot be used as a return air path for commercial applications (smoke control), but for residential you should be ok. It shouldn't take long to find out. Call up the local code juridiction and get a copy of what it says, word for word. The inspector probably knows it just as well, and will call it a 'ruling' or 'judgement call', but be sure you know what you are talking about before tackling the issue.