Sarah,
The overlapped send section as I understand it is predicated on the following assumptions: 1. A number that is incomplete can not also be complete! If this guideline is not followed, an endpoint in a zone separate from those of the two endpoint 1234 and 12345 (say) that attempts to dial a number one digit at a time will NEVER be able to get through to 12345! 2. Numbers are unique. 3. A gatekeeper will know from the format and first part of a number how long it should be.
For example a gatekeeper might assume that if a number is not in its own zone (and therefore known by it) then to stand any chance it will have to be a full international number, whose format and length are specified in E.164.
Public numbering plans do need to be covered as part of the Annex G effort, if we are going to attempt to do anything meaningful there with phone number-type addresses (as opposed to emailid-type addresses). Unfortunately the political minefield is considerable. In the meantime some sort of special knowledge on the part of each gatekeeper is assumed.
Regards, Chris -- Dr Chris Purvis - Senior Development Engineer, WAVE CC Software Madge Networks Ltd, Wexham Springs, Framewood Road, Wexham, Berks. Phone:+44 1753 661359 email: cpurvis@madge.com