When you run openafs for instance to mount you http://hcoop.net/ files with AFS, you can get the following error:

afsd: ERROR: Cache dir check failed (must use ext2 or ext3 for cache partition)

This happens when /var/cache/openafs doesn't reside on an ext2 or ext3 volume.

To solve this, since the /boot partition must be ext2 or ext3 currently for GRUB to boot:

# rm -r /var/cache/openafs
# mkdir /boot/var-cache-openafs
# ln -s /boot/var-cache-openafs /var/cache/openafs

Now afsd can be restarted and it'll start without errors:

# /etc/init.d/afsd restart