Rails - Mar 2006 - undefined method `crypted_password='' while using Sentry

I''d like to hear from some one who has been using Sentry successfully.
I am trying to
symmetrically_encrypts :password
for a user model. It is a bare bones model just to test Sentry. I have
password defined as ''text'' in the users table. I have openssl
library
installed on Debian Sarge. The secret key is defined in
environment.rb. But when I submit the form I get
undefined method `crypted_password=''

Thanks,

bakki