I just configured 'auto qos voip' on a 12.4T 
router's FastEthernet interface. The documentation claims this is impossible, which would seem strange since Catalyst IOS supports it on Ethernet switchports, so I verified. Can you confirm any other exceptions to its supposed restrictions? If FE works I suspect other Ethernet technologies will work--Ethernet, GigabiEthernet, and TenGigE. I'm also guessing that PoS is golden since PPP is running underneath.
General Restrictions
- The AutoQoS for the Enterprise feature is supported on the following interfaces, data-link connection identifiers (DLCIs), and permanent virtual circuits (PVCs) only:
- Serial interfaces with PPP or High-Level Data Link Control (HDLC)
 
- Frame Relay DLCIs in point-to-point subinterfaces only
 
- ATM PVCs
 
 
The AutoQoS for the Enterprise feature is supported on low-speed and high-speed ATM PVCs in point-to-point subinterfaces.