diff --git a/lib/capistrano/configuration/servers.rb b/lib/capistrano/configuration/servers.rb
index a412ced4..76df3e82 100644
--- a/lib/capistrano/configuration/servers.rb
+++ b/lib/capistrano/configuration/servers.rb
@@ -54,13 +54,14 @@ module Capistrano
             filter_server_list(hosts.uniq)
           end
         else
-					roles = role_list_from(ENV['ROLES'] || options[:roles] || self.roles.keys)
-					roles = roles & Array(options[:roles]) if preserve_roles && !options[:roles].nil?
+          roles = role_list_from(ENV['ROLES'] || options[:roles] || self.roles.keys)
+          roles = roles & Array(options[:roles]) if preserve_roles && !options[:roles].nil?
 
           only   = options[:only] || {}
           except = options[:except] || {}
           
-          servers = roles.inject([]) { |list, role| list.concat(self.roles[role]) }
+          # If we don't have a def for a role it means its bogus, skip it so higher level can handle
+          servers = roles.inject([]) { |list, role| list.concat(self.roles[role] || []) }
           servers = servers.select { |server| only.all? { |key,value| server.options[key] == value } }
           servers = servers.reject { |server| except.any? { |key,value| server.options[key] == value } }
 
@@ -103,7 +104,6 @@ module Capistrano
         roles = build_list(roles)
         roles.map do |role|
           role = String === role ? role.strip.to_sym : role
-          raise ArgumentError, "unknown role `#{role}'" unless self.roles.key?(role)
           role
         end
       end
diff --git a/test/configuration/servers_test.rb b/test/configuration/servers_test.rb
index 6e30bb76..726c1521 100644
--- a/test/configuration/servers_test.rb
+++ b/test/configuration/servers_test.rb
@@ -39,11 +39,11 @@ class ConfigurationServersTest < Test::Unit::TestCase
     assert_equal %w(web1 web2).sort, @config.find_servers_for_task(task).map { |s| s.host }.sort
   end
 
-  def test_task_with_unknown_role_should_raise_exception
+  # NOTE Rather than throw an error, as it used to, we return an
+  #  empty array so that if a task is okay with a missing role it can continue on
+  def test_task_with_unknown_role_should_return_empty_array
     task = new_task(:testing, @config, :roles => :bogus)
-    assert_raises(ArgumentError) do
-      @config.find_servers_for_task(task)
-    end
+    assert_equal [], @config.find_servers_for_task(task)
   end
 
   def test_task_with_hosts_option_should_apply_only_to_those_hosts