Perhaps found the real reason for the problem now:
ecryptfs-unwrap-passphrase /home/.ecryptfs/gunter/.ecryptfs/wrapped-passphrase
Passphrase:
XXXXXXXXXXXXXXXXXXXXXX
root@calcula:/home# ecryptfs-add-passphrase --fnek
Passphrase: [entered the passphrase from above here]
Error: Your kernel does not support filename encryption
Perhaps found the real reason for the problem now:
ecryptfs- unwrap- passphrase /home/. ecryptfs/ gunter/ .ecryptfs/ wrapped- passphrase XXXXXXX add-passphrase --fnek
Passphrase:
XXXXXXXXXXXXXXX
root@calcula:/home# ecryptfs-
Passphrase: [entered the passphrase from above here]
Error: Your kernel does not support filename encryption
Why this error message did happen?