Ah, I assumed that qpid::amqp was specific to the new amqp support code.
My mental model was that you had chosen to call the new amqp 1.0 support just qpid::amqp because it supports the official standardised protocol rather than the pre-standard 0.10 etc. versions - this makes reasonable sense to me.
But if I look at the code in qpid::amqp much of it is actually 1.0 specific irrespective of which library it gets built into.
At present the only place in the current tree which isn't protocol specific and is shared between broker and client is qpid::sys which isn't a good name at all (and there is indeed stuff in there that isn't actually shared!)
It would definitely be good to have a good set of rules about what goes where in the tree and then to move everything to suit.