Rails - Mar 2006 - [Sentry]-before_validation(model) not working for crypted-attribute?

I am still trying to get sentry working to encrypt a couple of
attributes in the model. One of them is a password field and the other
ssn#.

I have crypted_password and crypted_ssn in the db.
In addition, I also have validates_uniqueness_of :ssn

Here is the problem... I get the error
MysqlError: Unknown column ''ssn'' in ''where
clause'': SELECT * FROM
students WHERE (ssn = ''123-45-6789'')  LIMIT 1

THe stack trace shows that...
.../active_record/connection_adapters/abstract_adapter.rb:88:in `log''
.../active_record/connection_adapters/mysql_adapter.rb:180:in `execute''
.../active_record/connection_adapters/mysql_adapter.rb:322:in `select''
.../active_record/connection_adapters/mysql_adapter.rb:171:in
`select_all''
.../active_record/base.rb:431:in `find_by_sql''
.../active_record/base.rb:395:in `find''
.../activerecord-1.13.2/lib/active_record/base.rb:393:in `find''
.../activerecord-1.13.2/lib/active_record/validations.rb:502:in
`validates_uniqueness_of''

THe before_validation code in sentry is not substituting crypted_ssn
for ssn and also is not providing the encrypted value to the
validation code so that the table can be searched for uniqueness.

Can some one (please Rick :) shed some light on this for me? THank you
very much.

-bakki