billjw...
We just changed the way "0" routes internally at our site 2 weeks ago. There were a lot of problems with the old attendant console, and the new set up is skill-based routing, and working very well.
As 1Jumbo stated above, you do a ch dialplan ana, make 0 an ext. From there, you can create 0 as a VDN to vector, or station with coverage.
We created the agent, skill group and vectoring beforehand to test routing. The night of the change, I installed a pre-programmed 6424D+ with 24 button side car to replace the console. Now our call center supervisors can report (through CMS) on 0 and our main number.