TWRP 2.8.7 on Lolipop stock (just prerooted) can't mount encrypted system

I think the title says it all. On a almost totally stock z3c, TWRP can't access an encrypted /system - it asks for the pattern, but just says says the pass pattern'failed'. Changing to a PIN didn't help.

Recovery.log says:

Code:

---

E:Failed to decrypt data.
I:Set page: 'decrypt'
I:operation_end - status=1
I:Set page: 'trydecrypt'
I:operation_start: 'Decrypt'
Warning: crypto footer minor version 4, expected <= 3, continuing...
has_hw_crypto is 0
crypt_ftr->fs_size = 24719295
Using scrypt for cryptfs KDF
Enabling support for allow_discards in dmcrypt.
load_crypto_mapping_table: target_type = crypt
load_crypto_mapping_table: real_blk_name = /dev/block/mmcblk0p25, extra_params = 1 allow_discards
Error temp mounting decrypted block device '/dev/block/dm-0'
crypt_ftr->fs_size = 24719295
Using scrypt for cryptfs KDF
Enabling support for allow_discards in dmcrypt.
load_crypto_mapping_table: target_type = crypt
load_crypto_mapping_table: real_blk_name = /dev/block/mmcblk0p25, extra_params = 1 allow_discards
Error temp mounting decrypted block device '/dev/block/dm-0'
E:Failed to decrypt data.
I:Set page: 'decrypt'
I:operation_end - status=1

---

Is there an alternative build of TWRP I need or something ? The TWRP 3.x release thread makes it look like it's in no shape to try.

from xda-developers http://ift.tt/1RFiux5
via IFTTT