Last week (20th August) Amazon Web Services released Amazon Elastic Block Store (EBS). Amazon EBS provides block level storage volumes for use with Amazon EC2 instances. Amazon EBS volumes are off-instance storage that persists independently from the life of an instance. Amazon Elastic Block Store provides highly available, highly reliable storage volumes that can be attached to a running Amazon EC2 instance and exposed as a device within the instance. Amazon EBS is particularly suited for applications that require a database, file system, or access to raw block level storage.
This is a follow up to my posting, http://blog.mohanjith.net/2008/02/amazon-ec2-with-rock-solid-persistent.html. The method described there is obsolete with the release of Amazon EBS. None the less you can place the jail file system inside the EBS block device and not worry about having to build AMIs from time to time.
Hope this information helps someone.