Anyone else having issues with iTunes 8.2.1 in InstaDMG?

The last remaining issue I'm trying to iron out in my build train is iTunes; specifically, the Mobile Device Support. For some reason, it doesn't appear that the postinstall script in that package is running properly. As a result, the _usbmuxd user and group are not being created properly, which is causing the daemon that uses that to flip out and flood the console with error messages. Anyone else having any similar issues with this particular installer? eta: this is in InstaDMG r211.