I have a PPC-6600 on Sprint, and No. Sprint just dials speed dial one or a menu option for Voice mail. It dials the phone's number, but you are never asked for a passcode.

Still, putting P or W in the string does nothing. If I put it in it dials the first portion, but I cannot seem to release the rest!?!?

Pissing me off, b/c I dial a call center and have to manually put in an ID code everytime.

-BD