Redmine

I get the error: "Ha ocurrido un error mientras enviando el correo (getaddrinfo: Name or service not known)"

I'm using Redmine 2.0 stable with the following gemset:

actionmailer (3.2.3)
actionpack (3.2.3)
activemodel (3.2.3)
activerecord (3.2.3)
activeresource (3.2.3)
activesupport (3.2.3)
arel (3.0.2)
builder (3.0.0)
bundler (1.1.3)
coderay (1.0.6)
daemon_controller (1.0.0)
erubis (2.7.0)
fastthread (1.0.7)
hike (1.2.1)
i18n (0.6.0)
journey (1.0.3)
json (1.7.3)
mail (2.4.4)
mime-types (1.18)
multi_json (1.3.5)
net-ldap (0.3.1)
passenger (3.0.12)
pg (0.13.2)
polyglot (0.3.3)
prototype-rails (3.2.1)
rack (1.4.1)
rack-cache (1.2)
rack-openid (1.3.1)
rack-ssl (1.3.2)
rack-test (0.6.1)
rails (3.2.3)
railties (3.2.3)
rake (0.9.2.2)
rdoc (3.12)
rmagick (2.13.1)
ruby-openid (2.1.8)
rubygems-bundler (1.0.0)
rvm (1.11.3.3)
sprockets (2.1.3)
sqlite3 (1.3.6)
thor (0.14.6)
tilt (1.3.3)
treetop (1.4.10)
tzinfo (0.3.33)

My email configuration is:
production:
email_delivery:
delivery_method: :smtp
smtp_settings:
tls: true
enable_starttls_auto: true
address: "smtp.gmail.com"
port: '587'
domain: "smtp.gmail.com" # 'your.domain.com' for GoogleApps
authentication: :plain
user_name: "<user@gmail.com>"
password: "<password>"