I assume this can't be done: 
Error message:

".../Users/darkodosenovic/.gem/ruby/2.0.0/gems/capistrano-2.15.5/lib/capistrano/configuration/namespaces.rb:193:in `method_missing': undefined local variable or method `campfire_account' for #<Capistrano::Configuration::Namespaces::Namespace:0x007f89ac089868> (NameError)..."