BETA4 installer doesn't attach my HDD controller; BETA3 did

I've got a Maxtor 6Y080L0 YAR41VW0 drive on a JMicron JMB368 UDMA133  
controller, and in the BETA4 installer the controller doesn't seem to  
be properly attaching, which leads to the drive not being found.  The  
relevant sections from dmesg (as I'm not sure where else to look while  
running the installer CD) are:

 From BETA3:
atapci0: <JMicron JMB368 UDMA133 controller> port  
0xdc00-0xdc07,0xd880-0xd883,0xd800-0xd807,0xd480-0xd483,0xd400-0xd40f  
irq 16 at device 0.0 on pci2
atapci0: [ITHREAD]
ata2: <ATA channel 0> on atapci0
ata2: [ITHREAD]

 From BETA4:
atapci0: <JMicron JMB368 UDMA133 controller> port  
0xdc00-0xdc07,0xd880-0xd883,0xd800-0xd807,0xd480-0xd483,0xd400-0xd40f  
irq 16 at device 0.0 on pci2
atapci0: [ITHREAD]
device_attach: atapci0 attach returned 6

I've tried this with both i386 and amd64 install discs, with the same  
results.  I've googled and found many instances of people complaining  
about the "attach returned 6" thing, but without any solutions, so any  
help is greatly appreciated!  If there's more information I can give,  
please let me know what.

Thanks.


Todd