To choose from multiple email address while sending mail

Hi,   I want the user to have the facility to choose from which of his email address he wants to send the mail.

example a user may wish to send mail from abcd5675@yahoo.com or test54353@gmail.com or from some other email address. How do i configure action mailer seetings to handle this. MY current actionmailer settings as follows allow me to send mail only from one email address.

config.action_mailer.raise_delivery_errors = true

#set delivery method to :smtp, :sendmail or :test config.action_mailer.delivery_method = :smtp

#these options are only needed if you choose smtp delivery config.action_mailer.smtp_settings = {   :address => "mail@abcd.com",   #:domain =>'netsolmail.net',   :port => 25,   :authentication => :login,   :user_name => Username goes here,   :password => password goes here

}

Please help

And Also i believe for sending email through gmail tls is required. So how should i go about it also.

Thank you