Description: Some external USB drives take a longer time to start. In these conditions, it's corresponding device blocks have not time to populate /dev, although rc.sysinit tries to map crypttab entries, or to check and mount them.
The solution is to wait for each device to appear in /dev using a more elegant function than 'sleep 5'.


Additional info:
* package version: 2009.08-1
* config and/or log files:
- default rc.sysinit script
- crypttab containing entries like:
+ # NAME SOURCE DEVICE PASSWORD OPTIONS
+ external /dev/sdb1 /path/to/external.key
...where /dev/sdb1 is a LUKS partition on an external USB disk, in my case Seagate FreeAgent Desktop
- the boot error attests that the device blocks are not found (no such file...)
- fsck and mount fail and the system falls to maintenance prompt.


Steps to reproduce:
- plug-in an external drive with a LUKS partition
- add an entry in /etc/crypttab to open the partition at startup using a key file
- reboot
Note that the bug might not be reproductible with responsive drives.

I'm attaching the sysinit file I currently use, I modified the crypttab part in it only, but it should be used for fsck and other operations requiring USB disks as well, imo:
- function: lines 158 - 174
- usage: line 190