MirOS #10-current: support code for 256 byte inodes has been reverted (backed out) due to regressions wrt. 128 byte inode filesystems.
MirOS #8, #9, #10, #10-current: It is advised to refrain from using the ext2fs filesystem, especially in read-write mode, because symlink code is broken. The filesystem, and all processes accessing it, become unresponsive (hang in D state) upon creation of a symbolic link or access of a filesystem where such a broken symlink(7) is created. MirOS #7 can be used to access filesystems such as these, but the broken symlinks can still not be accessed by penalty of a kernel panic(9).
MirOS #10-current: ext2fs will be mounted read-only by default for now, starting 2009-04-23, until these problems are fixed.
MirOS (recent but unknown versions): the async mount flag ceased to work as it did before, says bsiegert@
MirOS #7quater: Not affected.