The ext2 bug has already been reported and a patch proposed:
http://lists.debian.org/debian-knoppix/2005/12/msg00028.html
I found a way to patch the knoppix-autoconfig file
(being part of the 700MB KNOPPIX cloop file) to fix the ext2
persistent disk problem, only using the minirt boot ramdisk.
(no need to remaster the KNOPPIX file nor to redownload the iso)
cf: http://www.knoppix.net/forum/viewtopic.php?p=98940#98940
The minirt_usb4.gz file also includes other features as:
iso boot from fat/ext/ntfs/reiser,
iso auto search when wrong disk device is used,
usb2 fix (high speed mode is now enabled, previously only USB1),
alternate hostname (to replace the Knoppix hostname
and also dynamic hostnames using time and mac address)
Hope this help,
Gilles