Redmine

Hi friends,
i installed redmine through source package ;;using wiki i configured Email notification in redmine ;;; but it's occurs error
while sending test mail

"An error occurred while sending mail (530 5.7.0 Must issue a STARTTLS command first. u10sm4937625pbr.12 )"

1. File: config/email.yml
   production:
   delivery_method: :smtp
   smtp_settings:
2. tls: true
   address: "smtp.gmail.com"
   port: '587'
   domain: "smtp.gmail.com"
   authentication: :plain
   user_name: "test@gmail.com"
   password: "test"
   tls: true
   development:
   delivery_method: :smtp
   smtp_settings:
3. tls: true
   address: "smtp.gmail.com"
   port: '587'
   domain: "smtp.gmail.com"
   authentication: :plain
   user_name: "test@gmail.com"
   password: "test"
   tls: true

any help is appreciated!!!

with regards
Vijith P A