Mail server - if you don't have one on your machine, you can tell Wagn to use another mail server by adding something like this to wagn.rb:

ActionMailer::Base.smtp_settings = {
:address => "smtp.wherever.com",
:user_name => "...",
:password => "...",
:domain => "",
:authentication => :login
}
If you don't need authentication, you can skip the last four(?) lines in the squiggly brackets.