ArgumentError - Unable to rectify please help


I am stuck in a problem which I am unable to understand. I am trying to
send an email, which I have done before, after user registers himself on
a website. User provides email address which he has to confirm before
getting any further communication. I have to do three things before the
user object is saved, like creating some other records and sending email
to confirm email, in a transaction. But, rails is throwing some error
(ArgumentError (interning empty string)) while calling
Mailer.deliver_confirm(email, code).

The stack trace is at

Please provide suggestions as where I am going wrong. I am using
Rails-2.3.2 and Ruby-1.8.7 this time.

What's going on in line 105 of accounts_controller.rb? Also, is there
any information in the log file that corresponds to the failure?