Modified the text at the end of Section 4.3.3 to be clear about which options
use Q-mode and which do on. Revised text:

   If a messaging association is not required, the message is sent in
   D-mode.  The processing in this case depends on the message type and
   whether routing state exists or not.

   o  If the message is not a Query, and routing state exists, it is
      sent with the normal D-mode encapsulation directly to the address
      from the routing state table.

   o  If the message is a Query, then it is sent in Q-mode as defined in
      (Section 5.3.2); the details depend on the message routing method.

   o  If no routing state exists, GIST can attempt to use Q-mode as in
      the Query case.  If this is not possible, e.g. because the
      encapsulation for the MRM is only defined for one message
      direction, then this is an error condition which is reported back
      to the local signalling application.

From Lisa Dusseault:

Section 4.3.3, last three bullet points.  This is an example of the need to use
the "Q-mode" terminology consistently.  I can't tell if the first bullet point
means "use Q-mode", or the second bullet point, as well as the third.