I think it's fair to say your question has been answered, but just out of interest why would you want more than a couple of BT sockets in this day and age when landlines, especially wired ones, are somewhat old hat?
If you're wanting to use them for data (broadband, sky box, HDMI etc) most people get a load of RJ45 data sockets wired in cat5 or similar, wired back to a media cupboard. That way you have the flexibility to use each socket for whatever you want depending on how you patch it.
Some people call it "future-proofing" although I hate that expression.