signal voltage question

["Wyatt C. Francis" <wcf1@Ra.MsState.Edu>]

This is probably a simple question to answer, but I wanted to verify
something out of the PCI spec (Rev2.1).

If there is a 3.3V device that is 5V tolerant and it's outputs are at 3.3V
levels, even though the 3.3V levels are within the 5V specs, this still
isn't compliant, correct?  
(For example, some of the Altera 3.3V devices, that support the 5.0V PCI
bus.)

I wasn't sure since the spec. says "The signaling environments cannot be
mixed; all components on a given PCI bus must use the same signaling
convention of 5V or 3.3V."

Even though this may not be compliant, has anybody had any experience on
using a device like this?

Thanks,
Wyatt