API : How can I register a Maya Developer Node ID Block?

When making custom node types via scripted-plugins (or regular 'ol compiled plugins), they need a MTypeId set to a specific value, so that custom node types won't clash:

import maya.OpenMaya as om
kPluginNodeId = om.MTypeId(0x00113)

Autodesk divvies-out ranges of addresses to developers, but how do you get these addresses assigned?
Via this web site:
http://discussion.autodesk.com/cgi-bin/maya/MayaID.cgi