Redmine

Hi all,

Im trying to implemet our smtprelay server to the redmine server.
That is my config:

production:
email_delivery:
delivery_method: :smtp
smtp_settings:
address: mysmtprelay.mydomain.com
port: 25
domain: mydomain.com
This config i found here:
http://www.redmine.org/projects/redmine/wiki/EmailConfiguration

this is the only part i have edit in the configuration.yml all other parts are not enabled

but unfortunately if i try to send a testmail i get this erro message: An error occurred while sending mail (getaddrinfo: Temporary failure in name resolution)
That is my Environment:
Redmine version 2.2.3.stable.11369
Ruby version 1.9.3 (x86_64-linux)
Rails version 3.2.12
Environment production
Database adapter Mysql2
Redmine plugins:
no plugin installed

any idea what im doing wrong?

thank you all