tcplay: cannot mount filesystem on TrueCrypt volume with hidden volume protection after mapping it

I am using tcplay to work with a Truecrypt volume with a 4 GB hidden volume located at the final gigabyte. When I mount either the normal volume or the hidden volume, they mount just fine. However, when I mount the normal volume with hidden volume protection (option --protect-hidden, or in short form, -e), this is what I get: [root@oc2222167007 /media]# tcplay -m truecrypt2 -e -d /dev/loop0 Passphrase: Passphrase for hidden volume: All ok! [root@oc2222167007 /media]# parted -l | grep -B1 -A5 truecrypt Error: /dev/mapper/truecrypt2: unrecognised disk label When I mount the filesystem with -e, it won't pick it up... [root@oc2222167007 /media]# cryptsetup remove truecrypt2 [root@oc2222167007 /media]# tcplay -m truecrypt2 -d /dev/loop0 Passphrase: All ok! [root@oc2222167007 /media]# parted -l | grep -B1 -A5 truecrypt Model: Linux device-mapper (crypt) (dm) Disk /dev/mapper/truecrypt2: 4295MB Sector size (logical/physical): 512B/512B Partition Table: loop Number Start End Size File system Flags 1 0.00B 4295MB 4295MB ext4 ...but if I mount the external volume just like that, it works fine. What's happening?