Hi, I am a professional perl/shell programmer with 7 years experiences, I believe I am qualified because I have worked on projects very similar to your requirements, the most recent one was to extract 25000+ user information from excel files and prepare regeneration data(user name, password, address, gender etc) to register on a PHP based website, then sign in with registered user, apply to join in different user groups according to user's address. The PHP website maintains cookie for each loggin session.
Please don't hesitate to contact me for further discussion, thanks!