diff --git a/app/logical/email_validator.rb b/app/logical/email_validator.rb
index 7af1bbda3..313248be6 100644
--- a/app/logical/email_validator.rb
+++ b/app/logical/email_validator.rb
@@ -63,6 +63,10 @@ module EmailValidator
     "gmx.us" => "gmx.net",
   }
 
+  def smtp_enabled?
+    Rails.env.production?
+  end
+
   def normalize(address)
     return nil unless address.count("@") == 1
 
diff --git a/test/unit/email_validator_test.rb b/test/unit/email_validator_test.rb
index cf1bf0557..77392c08c 100644
--- a/test/unit/email_validator_test.rb
+++ b/test/unit/email_validator_test.rb
@@ -2,6 +2,10 @@ require 'test_helper'
 
 class EmailValidatorTest < ActiveSupport::TestCase
   context "EmailValidator" do
+    setup do
+      EmailValidator.stubs(:smtp_enabled?).returns(true)
+    end
+
     context "#undeliverable?" do
       should "return good addresses as deliverable" do
         assert_equal(false, EmailValidator.undeliverable?("webmaster@danbooru.donmai.us"))