Comment 1 for bug 1020022

This appears to be script which contains IDs of base AMIs used by cbuild:

http://bazaar.launchpad.net/~linaro-toolchain-dev/cbuild/tools/view/head:/ec2-spawn.sh

spawn oort1 ami-fd589594 c1.xlarge
099720109477/ebs/ubuntu-images/ubuntu-natty-11.04-amd64-server-20111003

spawn oort3 ami-a29943cb c1.xlarge
ubuntu/images/ebs/ubuntu-precise-12.04-amd64-server-20120424

spawn oort2 ami-e358958a c1.medium
ebs/ubuntu-images/ubuntu-natty-11.04-i386-server-20111003

spawn oort12 ami-37af765e c1.medium
ubuntu/images/ebs/ubuntu-lucid-10.04-i386-server-20120403

So, all base images are at least EBS ones.