Recurrence of the access problems issue - 10.5.3 to OS X, Linux

"The folder could not be opened because you do not have sufficient access privileges" pops up for all mounted drives.

My username is the same on two of the four systems. My group ID is different from three other machines' GID. Three are OS X 10.5.3, one is RHEL4.

Doing a ls -l on /Volumes shows lines like this for the disks:

d????????? ? ? ? ? SampleDisk

and for the four, the results of python -c "import os; print os.statvfs('.')"

are:
OS X: (1048576, 4096, 19453708L, 3347799L, 3283799L, 19453706L, 3283799L, 3283799L, 0, 255)
OS X: (1048576, 4096, 19453708L, 3347758L, 3283758L, 19453706L, 3283758L, 3283758L, 0, 255)
OS X: (1048576, 4096, 122012668L, 36936884L, 36872884L, 122012666L, 36872884L, 36872884L, 0, 255)
RHEL4: (4096, 4096, 12598749, 11031169, 10391180, 6406144, 6230060, 6230060, 0, 255)

This is in ExpanDrive 1.2.2, and also happens in the 6/23 nightly. I had MacFUSE installed before, but was not using it at the time of install. I did reboot the machine to see of things got better, but they still fail.

I bought a license because my boss had a problem-free experience. :) I want one too.