I really hate closed source systems, every time I have to deal with it, it turns out to be a waste of time dealing with it. Right now I’m dealing with a closed source BSS (I wish I could call names), I can make it fail by sending a very simple message, a message that is crucial for everything (SMS, Call) to terminate on the MS. Of course an expensive support contract was signed but apparently it does not buy more than the right to create a ticket in a bug tracker and let it rot there. Never ever make your business depend on a black box!