Boot hangs on IVM xSeries 342

I've been attempting to install version 5.0 on an IBM xSeries 342 and
having problems with the system hanging while booting.  If I boot from
the install CD the system hangs.  It will install successfully when
doing the install boot from floppies and using FTP, since it does not
see the CD drive after booting from floppies, but then hangs when
booting from the hard drive, at the same point as when booting off
the install CD.  I was able to install 4.7 successfully and it
functioned OK under 4.7, and 4.8-RC.  I wanted to see if anyone else
had seen this before I started trying to selectively add/remove drivers
to narrow down possibilities.  I've attached a log of the boot, it
progresses normally to through the vga0: line, then the last three
come after waiting for several minutes.

/boot/kernel/kernel text=0x3d01ec data=0x50fc0+0x5aba4 syms=[0x4+0x4dcf0+0x4+0x5bd3e]

Hit [Enter] to boot immediately, or any other key for command prompt.
Booting [/boot/kernel/kernel]...               
/boot/kernel/acpi.ko text=0x3985c data=0x1978+0xb28 syms=[0x4+0x6010+0x4+0x7994]
Copyright (c) 1992-2003 The FreeBSD Project.
Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
        The Regents of the University of California. All rights reserved.
FreeBSD 5.0-RELEASE #0: Thu Jan 16 22:16:53 GMT 2003
    root_at_hollin.btc.adaptec.com:/usr/obj/usr/src/sys/GENERIC
Preloaded elf kernel "/boot/kernel/kernel" at 0xc0673000.
Preloaded elf module "/boot/kernel/acpi.ko" at 0xc06730a8.
Timecounter "i8254"  frequency 1193182 Hz
Timecounter "TSC"  frequency 1393301249 Hz
CPU: Pentium III/Pentium III Xeon/Celeron (1393.30-MHz 686-class CPU)
  Origin = "GenuineIntel"  Id = 0x6b1  Stepping = 1
  Features=0x383fbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,MMX,FXSR,SSE>
real memory  = 2415833088 (2303 MB)
avail memory = 2345443328 (2236 MB)
Initializing GEOMetry subsystem
Pentium Pro MTRR support enabled
npx0: <math processor> on motherboard
npx0: INT 16 interface
acpi0: <IBM    SERQURTZ> on motherboard
    ACPI-0625: *** Info: GPE Block0 defined as GPE0 to GPE31
acpi0: power button is handled as a fixed feature programming model.
Timecounter "ACPI-safe"  frequency 3579545 Hz
acpi_timer0: <24-bit timer at 3.579545MHz> port 0x4e8-0x4eb on acpi0
acpi_cpu0: <CPU> on acpi0
acpi_cpu1: <CPU> on acpi0
pcib0: <ACPI Host-PCI bridge> on acpi0
pci0: <ACPI PCI bus> on pcib0
xl0: <3Com 3c905-TX Fast Etherlink XL> port 0x2000-0x203f irq 11 at device 1.0 on pci0
xl0: Ethernet address: 00:60:08:9f:a9:e6
miibus0: <MII bus> on xl0
nsphy0: <DP83840 10/100 media interface> on miibus0
nsphy0:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
pci0: <display, VGA> at device 6.0 (no driver attached)
isab0: <PCI-ISA bridge> port 0x440-0x44f at device 15.0 on pci0
isa0: <ISA bus> on isab0
atapci0: <ServerWorks ROSB4 ATA33 controller> port 0x840-0x84f at device 15.1 on pci0
ata0: at 0x1f0 irq 14 on atapci0
ata1: at 0x170 irq 15 on atapci0
ohci0: <OHCI (generic) USB controller> mem 0xfeb7f000-0xfeb7ffff irq 10 at device 15.2 on pci0
usb0: OHCI version 1.0, legacy support
usb0: <OHCI (generic) USB controller> on ohci0
usb0: USB revision 1.0
uhub0: (0x1166) OHCI root hub, class 9/0, rev 1.00/1.00, addr 1
uhub0: 4 ports with 4 removable, self powered
pcib1: <ACPI Host-PCI bridge> on acpi0
pci1: <ACPI PCI bus> on pcib1
fxp0: <Intel Pro 10/100B/100+ Ethernet> port 0x2040-0x207f mem 0xeffc0000-0xeffdffff,0xeffff000-0xefffffff irq 15 at device 7.0 on pci1
fxp0: Ethernet address 00:09:6b:b0:83:96
inphy0: <i82555 10/100 media interface> on miibus1
inphy0:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
pcib2: <ACPI Host-PCI bridge> on acpi0
pci2: <ACPI PCI bus> on pcib2
ahc0: <Adaptec aic7899 Ultra160 SCSI adapter> port 0x2100-0x21ff mem 0xedfff000-0xedffffff irq 9 at device 9.0 on pci2
aic7899: Ultra160 Wide Channel A, SCSI Id=7, 32/253 SCBs
ahc1: <Adaptec aic7899 Ultra160 SCSI adapter> port 0x2200-0x22ff mem 0xedffe000-0xedffefff irq 9 at device 9.1 on pci2
aic7899: Ultra160 Wide Channel B, SCSI Id=7, 32/253 SCBs
atkbdc0: <Keyboard controller (i8042)> port 0x64,0x60 irq 1 on acpi0
atkbd0: <AT Keyboard> flags 0x1 irq 1 on atkbdc0
kbd0 at atkbd0
psm0: <PS/2 Mouse> irq 12 on atkbdc0
psm0: model IntelliMouse, device ID 3
fdc0: <Enhanced floppy controller (i82077, NE72065 or clone)> port 0x3f7,0x3f0-0x3f5 irq 6 drq 2 on acpi0
fdc0: FIFO enabled, 8 bytes threshold
fd0: <1440-KB 3.5" drive> on fdc0 drive 0
sio0 port 0x3f8-0x3ff irq 4 on acpi0
sio0: type 16550A, console
sio1 port 0x2f8-0x2ff irq 3 on acpi0
sio1: type 16550A
orm0: <Option ROMs> at iomem 0xcc800-0xd0fff,0xcb000-0xcc7ff,0xc0000-0xcafff on isa0
pmtimer0 on isa0
ppc0: parallel port not found.
sc0: <System console> at flags 0x100 on isa0
sc0: VGA <16 virtual consoles, flags=0x100>
vga0: <Generic ISA VGA> at port 0x3c0-0x3df iomem 0xa0000-0xbffff on isa0
Timecounters tick every 10.000 msec
ata0-master: ATAPI identify retries exceeded
Waiting 15 seconds for SCSI devices to settle