diff --git a/lib/validates_timeliness/railtie.rb b/lib/validates_timeliness/railtie.rb
index 6b88d61..3c4cd5e 100644
--- a/lib/validates_timeliness/railtie.rb
+++ b/lib/validates_timeliness/railtie.rb
@@ -11,5 +11,13 @@ module ValidatesTimeliness
     initializer "validates_timeliness.initialize_restriction_errors" do
       ValidatesTimeliness.ignore_restriction_errors = !Rails.env.test?
     end
+
+    initializer "validates_timeliness.initialize_timeliness_ambiguous_date_format" do
+      if Timeliness.respond_to?(:ambiguous_date_format) # i.e. v0.4+
+        # Set default for each new thread if you have changed the default using
+        # the format switching methods.
+        Timeliness.configuration.ambiguous_date_format = Timeliness::Definitions.current_date_format
+      end
+    end
   end
 end
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index a75afd2..a09ec1c 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -9,6 +9,8 @@ require 'timecop'
 require 'validates_timeliness'
 require 'validates_timeliness/orm/active_model'
 
+require 'rails/railtie'
+
 require 'support/test_model'
 require 'support/model_helpers'
 require 'support/config_helper'
diff --git a/spec/validates_timeliness/railtie_spec.rb b/spec/validates_timeliness/railtie_spec.rb
new file mode 100644
index 0000000..b7dfacf
--- /dev/null
+++ b/spec/validates_timeliness/railtie_spec.rb
@@ -0,0 +1,22 @@
+require 'validates_timeliness/railtie'
+
+RSpec.describe ValidatesTimeliness::Railtie do
+  context "intializers" do
+    context "validates_timeliness.initialize_timeliness_ambiguous_date_format" do
+      it 'should set the timeliness default ambiguous date format from the current format' do
+        expect(Timeliness.configuration.ambiguous_date_format).to eq :us
+        ValidatesTimeliness.parser.use_euro_formats
+
+        initializer("validates_timeliness.initialize_timeliness_ambiguous_date_format").run
+
+        expect(Timeliness.configuration.ambiguous_date_format).to eq :euro
+      end
+    end if Timeliness.respond_to?(:ambiguous_date_format)
+
+    def initializer(name)
+      ValidatesTimeliness::Railtie.initializers.find { |i|
+        i.name == name
+      } || raise("Initializer #{name} not found")
+    end
+  end
+end