Feedback: PCI device spec

Greetings,  A colleague of mine, implementing a virtio PCI device now, asked me to pass some feedback on his behalf (a trick to avoid legals & IPR :-)  P. 6.1. "Configuration Space Organization" of the "PCI Local Bus Specification, REV. 3.0" (page 215) states that "All PCI compliant devices must support the [..] Class Code" and the WD01 does not define what class should it be.  I had a look at the spec and appendix D. "Class Codes" defines "00h Device was built before Class Code definitions were finalized" and a brief look at Linux kernel shows that it would work. At the same time native KVM tools use "01h Mass storage controller" with subclass/interface "80h 00h Other mass storage controller" which probably makes sense.  I'm far from being any kind of PCI expert, so the question is: Should the spec clarify this matter? Maybe a table in the PCI chapter showing virtio ID -> PCI class?  Pawel