Raid 1 + LVM + Encryption doesnt work 10.04

Hey,

First thing i need say is my english isnt so good, so i hope u guys can understand me.
I'm trying get working the setup: Raid 1 + Encryption + LVM
But seems this isnt working on Ubuntu and Debian also...
I'm using Ubuntu Server 10.04.3 LTS, the steps i did is:

One primary partition on both disks (sda / sdb) with boot flag
One Extend partition in both disks
One logical partition with the rest of space in both disks
I set both disks as raid (md0_raid1 / md1_raid1)
I set md0_raid1 for /boot since have the boot flag
I set md1_raid1 for encrypt volume
After encryption pass have be set, i start LVM on md1_raid1
On md1_raid1 i did partitons for /, /home, /etc, swap, /opt, /srv, /var

Got no issues on install, on disk manager inside of gnome desktop show the partitions are sync without problems...
Some hours later, everything seems ok, then i restart the server and get this message on every boot:

  /dev/dm-0: stat failed: No such file or directory
  Path /dev/dm-0 no longer valid for device(251,0)

So i turn off the server and removed the second disk (sdb), the system doesnt boot, i got this message:
lvm device name does not begin with/dev/mapper/
Once more time i turn off the server and this time i removed the first disk and plugged back the second disk, (sda off and sdb on)
The system doesnt boot too. (no message this time, only reboot)

I have setted degraded mode to yes already on installation
One wierd thing is when i use Menu / System / Administration / Disk util, i can see the partitions under periferical devices, but on Matrix RAID-1 i see one encrypted vol and an vol LVM2 not encrypted for the extend partition, this show like an full volume disk

Should i do the raid in other order in the installation?
I mean set the raid only after do the encryption and LVM is set (then raid inside of the LVM instead top of extend partition)?