diff --git a/lib/friendly_id/slug_string.rb b/lib/friendly_id/slug_string.rb
index 989fc9271..0e80e3b3b 100644
--- a/lib/friendly_id/slug_string.rb
+++ b/lib/friendly_id/slug_string.rb
@@ -191,7 +191,7 @@ def initialize(string)
       # @param *args <Symbol>
       # @return String
       def approximate_ascii!(*args)
-        @maps = (self.class.approximations + args + [:common]).flatten.uniq
+        @maps = (self.class.approximations + args.flatten + [:common]).flatten.uniq
         @wrapped_string = normalize_utf8(:c).unpack("U*").map { |char| approx_char(char) }.flatten.pack("U*")
       end
 
@@ -235,7 +235,7 @@ def word_chars!
       # @param config [FriendlyId::Configuration]
       # @return String
       def normalize_for!(config)
-        approximate_ascii! if config.approximate_ascii?
+        approximate_ascii!(config.ascii_approximation_options) if config.approximate_ascii?
         to_ascii! if config.strip_non_ascii?
         normalize!
       end
diff --git a/lib/friendly_id/test.rb b/lib/friendly_id/test.rb
index 84a33d17b..069d067d6 100644
--- a/lib/friendly_id/test.rb
+++ b/lib/friendly_id/test.rb
@@ -194,6 +194,19 @@ module Slugged
         end
       end
 
+      test "should approximate ascii if configured" do
+        klass.friendly_id_config.stubs(:approximate_ascii?).returns(true)
+        instance = klass.send(create_method, :name => "Cañón")
+        assert_equal "canon", instance.friendly_id
+      end
+
+      test "should approximate ascii with options if configured" do
+        klass.friendly_id_config.stubs(:approximate_ascii?).returns(true)
+        klass.friendly_id_config.stubs(:ascii_approximation_options).returns(:spanish)
+        instance = klass.send(create_method, :name => "Cañón")
+        assert_equal "cannon", instance.friendly_id
+      end
+
     end
 
     # Tests for FriendlyId::Status.