NVidia driver for amd64 / Page Attribute Table status?

Hi,

I have searched for some information about nVidia FreeBSD-amd64 driver 
and reasons why it is not availible, but the whole situation seems to be 
very mysterious.

There are comments on nVidia forums from september by mr. Zander from 
nVidia:
"There are technical problems with the FreeBSD/amd64 kernel that gate 
NVIDIA graphics driver support for this platform. NVIDIA has brought 
these problems up with FreeBSD developers and has been working with one 
of them to make reliable support for FreeBSD/amd64 technically possible, 
but unfortunately we can't provide a schedule for when this will be 
complete."
(http://www.nvnews.net/vbulletin/showthread.php?t=41545&page=2)

Both the developer and the 'technical problems with FreeBSD' are kept 
secret...
There are some clues in freebsd-current archive:
"There are a few missing VM features that any high-performance graphics 
card driver would require for decent performance with PCI Express. John 
is working on adding those features - have patience."

and

"Actually I think that the feature we are talking about (PAT) is 
relevant to both amd64 and i386. Proper support for PAT is required for 
decent PCI Express performance, as I understand it."

(http://lists.freebsd.org/pipermail/freebsd-current/2005-July/052740.html
http://lists.freebsd.org/pipermail/freebsd-current/2005-July/052746.html)

Is Page Attribute Table feature blocking nVidia drivers?
What is the status of this feature then?
Can someone informed enough shed some light on the story?

Thanks for Your time,
m.