4.9 ATA hangs with 2 ata drives

[J S Goldberg]

I've got both 4.9 and 5.1 loaded on my new ASUS A7N8X Deluxe
with two 160Gb disks on the primary ATA controller.  5.1 does
much better handling both ATA disks.  When I run 4.9 with the
second disk connected, it hangs during kernel boot after the
message:

ad1: READ command timeout tag=0 serv=0 - resetting
ata0: resetting devices  

I've seen what looks like similar problems in the archives (e.g.,
http://docs.freebsd.org/cgi/mid.cgi?188200406.20031109073901).
It seems to happen on various motherboards and disk configurations.
I wanted to provide another datapoint for configurations.

My 4.9 came from the CD image downloaded from the ftp site last
week (weds).  5.1 came from the subscription CD. 

The questions are:
1. Has anyone gotten a similar configuration working on 4.9?
2. Will it make a difference to CVSup?

Thanks in advance!
j