I have a similar USB Pendrive problem in Fedora 5 and Windows.
I have 2 usb Pendrives: one from Transcend(128 MB) Works properly.
I have another, a new one(512MB) from I-dont-know-who company.
This gets recognized first..then after a minute or so, the mount fails and I
get a bunch of
"device not accepting address " errors in syslog.
When I touch the USB device, I see its real hot.
But I remember this device working somewhat ok (even though it was very hot)
in Redhat 9.
(In windows, after a couple of minutes this drive is thrown out and get a
usb device removed improperly error.)
So I guess it might be worthwhile to test with a good USB pendrive and
confirm if things are ok with that. The issue being with the device and not
with your Drivers.
--hari