Comment 23 for bug 381920

unfortunately, this is not a bug completely, your mount options in fstab are not complete

real now it designed to work this way:
1) as root, mount your private directory
2) run mount, which will return mount options used including key signature(s)
3) put this options to /etc/fstab

when mounting, do:
ecryptfs-add-passphrase --fnek (if you are not using file name encryption, don't use "--fnek")
mount -i

but this is bug, because:
mlockall code is somehow broken
and this design seems little bit odd