Request.env availability

Hello everybody,

My application will run on different machines with different host
names. In most of my emails I have to include a link with the name of
the server the email is coming from. So, I decided to use the
request.env hash to get the server name. But request.env is not
available in ActionMailer. So, I have to pass that variable to each
mailing method from the controller, which doesn’t look too good.

Is there a better way? Can I hardcode the name of the server somewhere
in the configuration (environment.rb ?) and thus make it available