OMFS is the filesystem used internally by the Rio Karma. Following omfs-0.5.7, 0.5.8 and 0.6.0, omfs-0.6.1 is the first release providing fully correct (we hope ;) read/write/delete support. It definitively allows lkarmafs to work properly with both Rio Karma interfaces, USB and Ethernet.
Download: http://sourceforge.net/project/showfiles.php?group_id=155788&package_id=175124