I installed lessfs and moved a bunch of data into it. Recently I had a crash and had to reboot. When I got back up, I was apparently able to start lessfs ok - the drive mounts, and you can list directories, etc. But if you try to copy a file, say, the transport disconnects and you get the above in /var/log/messages.
This is lessfs 1.5.7, on Fedora 15 (with kernel 18.104.22.168-5.fc15.x86_64)