cryptsetup 2:1.4.3-4ubuntu4 is broken with luks based encryptions in saucy?

After upgrading to saucy, my laptop did not unlock the encrypted partitions, but driven me crazy and I was not able to fix the situation except downgrading the cryptsetup package to 2:1.4.3-4ubuntu2.

Partitions and config files:
- I have an encrypted luks partition, containing the root filesystem partition and a swap partition.
- I have the following config files:
/etc/crypttab:
sda5_crypt UUID=xxx none luks
/etc/initramfs-tools/conf.d/cryptroot:
CRYPTOPTS=target=sda5_crypt,source=UUID=xxx,lvm=yyy

If I have the latest cryptsetup installed, I am prompted for password, but unlocking fails because the initiramfs does not include the cryptsetup. Adding e.g CRYPTSETUP='y' to /etc/initramfs-tools/initramfs.conf does not change this behavior.

Although the man page of crypttab states: "On LUKS devices, the used settings are stored in the LUKS header, and thus don't need to be configured in /etc/crypttab.", if I remove the content of /etc/crypttab or delete /etc/initramfs-tools/conf.d/cryptroot, I am not prompted for password at all.