I have an mdadm raid 5, with 5 drives running for more that 1 year with no issues
Something really really bad happend and it's saying I just loose 3 drives
and don't let me add the other 3 saying "mdadm: /dev/sdc does not appear to be an md device"

here is how the mdadm looks now
mdadm: metadata format 00.90 unknown, ignored.
/dev/md0:
Version : 00.90
Creation Time : Sun Mar 15 03:49:03 2009
Raid Level : raid5
Used Dev Size : 976762368 (931.51 GiB 1000.20 GB)
Raid Devices : 5
Total Devices : 2
Preferred Minor : 0
Persistence : Superblock is persistent

Update Time : Sat Nov 20 16:23:39 2010
State : active, degraded, Not Started
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0

Layout : left-symmetric
Chunk Size : 512K

UUID : a8218870:64885bf0:e9110788:09b4438a
Events : 0.1715296

Number Major Minor RaidDevice State
0 8 0 0 active sync /dev/sda
1 8 16 1 active sync /dev/sdb
2 0 0 2 removed
3 0 0 3 removed
4 0 0 4 removed


I'm really really desperate.....
Thanks!