how to create an encrypted ext3 filesystem using "cryptsetup"?

[Dale]

On Mon, Jun 21, 2004 at 10:27:25AM -0400, Robert P. J. Day wrote:
[...]
>   at this point, based on the docs, i would run "cryptsetup", but there's 
> no incantation i've tried that works.  there's no man page for cryptsetup, 
> and everything i try comes back with:
> 
>   # cryptsetup ...
>   Command failed: invalid argument.
> 
> not overly helpful. :-P
> 
>   (by the way, given that "aes" is the default cipher, i figured out
> quickly that i needed to "modprobe aes" first.)
> 
>   so ... what's the rest of the recipe to get my encrypted FS?

The URL info from "rpm -qi cryptsetup" leads to
    http://www.saout.de/misc/dm-crypt/
which has information about cryptsetup.