CORBA35 — BiDir GIOP Policy Clarification

I am a little confused as to the scope of the BiDirPolicy in the 2.4.1
specification. Is the BiDirPolicy a POA policy, an ORB policy, or both? In
section 15.8 paragraph 5 on page 15-55, the specification states:

"If the client ORB policy permits bi-directional use
of a connection, a Request message should contain an IOP::ServiceContext
structure in its Request header, which indicates that this GIOP connection
is bi-directional."

but then in section 15.9 paragraph 4 on page 15-59, the specification
states:

"In the absence of a BidirectionalPolicy being passed in the
PortableServer::POA::create_POA operation, a POA will assume a policy value
of
NORMAL."

but then again in the next sentence the specification states:

"A client and a server ORB must each have a BidirectionalPolicy with a value
of
BOTH for bi-directional communication to take place."

Could someone clarify for me what the intent for the scope of the policy was
here, and what the rationale behind that decision was? We are currently
reviewing how to use/fix BiDirIIOP in our submission to the firewall RFP,
and I would like to understand the issues regarding the scope of the BiDir
policy.