Base internationalization and multiple storyboard not working right-Collection of common programming errors

I’m playing with multiple storyboards and base localization on xCode 4.6. In fact I

I did:

1) edit my project infos localisations: checked “Use Base Internationalization” and added Languages: English, Chinese

2) create a new storyboard called “anotherstoryboard.storyboard”

3) localize my new storyboard (File Inspector / Localize – Localize) using Base internationalization.

4) in my app delegate, I load dynamically my localized storyboard, like this:

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"anotherstoryboard" bundle:nil];

case 1: => works

For my new storyboard (step 3) I choose Localization Chinese – Interface Builder Cocoa Touch Storyboard

It works but now I have to maintain localized storyboard, editing them with IB. I don’t want such behavior, I just want to use base internationalization and localize .strings files.

case 2: => crashes

For my new storyboard (step 3) I choose Localization Chinese – Localizable Strings

The app crashes saying it can’t find my storyboard

'NSInvalidArgumentException', reason: 'Could not find a storyboard named 'anotherstoryboard' in bundle NSBundle  (loaded)'

What I’m doing wrong ? Why doesn’t iOS find the right storyboard in case 2 ?