Description of problem:
When booting my system about 30% of the time the boot fails and the last message shown is something like
systemd-cryptsetup: invalid packets

fdisk -l

Disk /dev/sda: 64.0 GB, 64023257088 bytes
255 heads, 63 sectors/track, 7783 cylinders, total 125045424 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x11e3f74a

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *          63      409662      204800   83  Linux
/dev/sda2          409663    24985662    12288000   83  Linux
/dev/sda3        24987648    29181951     2097152   82  Linux swap / Solaris
/dev/sda4        29181952   125044735    47931392   83  Linux

sda2 (/) and sda4 (/home) are encrypted with LUKS. Also note that sometimes the system asks for the passphrase only once (same passphrase used for both partitions) and sometimes a second prompt appears for unlocking /home.

No traces in /var/log/messages after reboot.

Version-Release number of selected component (if applicable):
systemd-24-1.fc15.i686
Same behaviour with f15 alpha and beta.

How reproducible:
30% of boots

Steps to Reproduce:
1. have / and /home encrypted with same passphrase during install
2.
3.