How can I access my USB flashdrive as the knoppix user instead of root?

Under knoppix 3.3, I create a directory with knoppix as owner & group, all permissions +rwx. But when I mount the usb drive, it changes the directory owner & group to root, and denies read/write access to knoppix.

As root, when I try to change the owner back to knoppix, I get "operation not permitted". Chmod +rwx on the directory (as root) doesnt work.

BTW here is the last line of /etc/fstab (not changed by me):
/dev/sda1 /usb vfat noauto,users,exec,umask=000,uid=knoppix,gid=knoppi x 0 0

Help!