Factory unlocked/Network unlocked but BBM/BIS wont work

So,there is this ebay seller claiming "the blackberry mobile is imported and factory unlocked/Network unlocked. Any gsm sim would work but BBM/BIS service were locked. i am from india.

What my question is why would BIS/BBM service wont work if the mobile is network unlocked/Factory unlocked or whatsoever. why only BB APP world would work and why not BBM ? when i asked the same, he said indian blackberry servers cant register the mobile as it is imported. Is that true ? please help me out. i'm stuck.

My guess it is an unlocked 9930 or such other world phones. Just get GSM and bis devices should be more than affordable locally...

thank you for responding. its a bold 9790.

And nothing else without the curly conditions available? You might have to spend a little more? Sounds like its a black listed device at country of origin.

I wonder if "BBM blocked" (as I've seen such phones advertised) is local for "PIN blocked."