Ok, I now see what you and Steve mean, that with those stupid REFERs in
the SIP protocol, attended and blind transfers are very different
things.

I'll try to explain this detail to my users (they were used to do blind
and attended xfers indifferently), and if they are unhappy I'll threaten
to re-install their old * PBX. This ultimate threat should garantee they
will stop using blind transfers right away!

Oh, and any way to disable blind xfers only?