ehci-hcd acpi hang in 8.1

After using online update to apply the latest kernel updates to my 8.1 kernel I find that my system can no-longer boot with acpi enabled. The boot processing hangs when hotplug tries to load the ehci-hcd module. Booting with acpi turned off in the kernel parameters allows the boot to complete successfully. The Motherboard is a Jetway with an Nvidia nForce chipset and an Athlon 2.2. Video card is a GeForce 2. Has anyone else come across this? Does anyone have a fix? P.S. Is there a searchable archive of this list anywhere? Roger