For via it should use ehci for 2.0 usb controller. According to this site.
http://www.usbman.com/linuxusb.htm
My lock up issue stopped when using kernel 2.4.22-rc2, but I never upgraded hotplug. At this release I could plug in my 2.0 usb harddrive and the system would not lockup. But I could not mount it. Upgraded hotplug to hotplug-base-2003_08_05-1_rh9.noarch.rpm and hotplug-2003_08_05-1_rh9.noarch.rpm. Then I could mount and use the drive.
I did an experiment and if I upgrade hotplug from a stock redhat 2.4.20-8 kernel My 2.0 usb devices mounted fine. Kudzu had to be dead and gone.
I would be curious to see if this would work with Geetoo. Anyways, good luck with the 2.6 kernels
Brian1