i just recently bought an unlocked blackberry curve 8310 from an Ebay purchase as i had signed a new contract and wasn't qualified for an upgrade.
Anyway, I added the BIS add on to the line.
In trying to set my phone up, it appears that the "setup email" application has been deleted. If I'm remembering correctly this is where you tell the blackberry that you're on a BIS plan.. However, because the device doesn't "know" its on a BIS plan it isn't letting me use the facebook application. I'm getting a message that reads in the facebook application that reads "You are currently on a service plan that does not support this application. Please contact your service provider yada yada yada".
This is the downside in buying a used Blackberry from a non-trusted source.
Firstly, contact the seller and make sure they have released their Blackberry from their carriers network. You should then be able to register yours. If not, and you still get the invalid PIN and IMEI message it may be that your BB has been hacked in which case you will need to return it for a refund.
If you get past the first step and manage to set up an account on your carrier's BIS site then you should be able to progress with the setting up of email and then downloading and using apps.
However it may be that this phone has been previously used in a BES environment and may still be subject to an IT policy. In which case there are excellent threads on the forum with regard to removing an IT policy and then you'd have the same control over your phone as if you'd bought it brand new.
