raid not booting

[Reinhard Haller]

Hi,

this morning my ubuntu box wasn't accessible (no local access, no ssh, 
no http -- ping worked), so I resetted the server.

The box didn't boot with the following messages:

There appears to be one or more degraded RAID devices ...

md0: incative sdc2[2](S) sdb2[1](S) sdc3[3](S)

The suggested start with the degraded raid (mdadm -R /dev/md0) gives the 
following messages:

mdadm: CREATE user root not found
mdadm: CREATE group disk not found
raid5: not enough operational devices for md0 (2/3 failed)

I tested all drives with the Samsung HD-Utility: they are all 3 fully 
operational, the partitions are all present!

Operating system: ubuntu 8.04 kernel: 2.6.24-18-server

Any suggestions how to get it working again?

Thanks
Reinhard