you mean http://www.fs-driver.org/ http://www.fs-driver.org/ ? ext3,ext4 are backwards compatible to ext2 (you lose journaling and some other nice features as y

you mean http://www.fs-driver.org/ http://www.fs-driver.org/ ? ext3,ext4 are backwards compatible to ext2 (you lose journaling and some other nice features as you roll back). When you revert to ext3/4 you usually end up having run a checkfs on boot though.