Ubunty 8.04 hangs when USB stick is plugged in
I am having a weird error intermittently when plugging a SanDisk U3 Cruzer Micro into an Ubuntu 8.04 system with the Edubuntu addon(s). Sometimes it will occur the first time I plug it in, other times I have had to plug, unplug, and plug it in again before it occurs, but at some point, the system hard freezes. I have booted into a rescue disk (SysRescCD) and examined the two newest versions of each of the system log files (dmesg, syslog, messages, and kern), but there is nothing suspicious at the end of any of them (I am using AppArmor with Firefox, so most of the messages are policy violation complaints, and before those are DHCP messages from immediately after boot). Also, if I plug in the drive before booting, the system doesn't even see it (lshw, lsusb).
I've googled this numerous times, and can't seem to find anything directly related to my problem: lots of people having trouble booting from USB hard drives, but I'm not trying to boot from it.
I'm fairly certain this isn't a problem with the device, as I use it often on other systems, and have never had this problem before.