diff --git a/test/test_ssl.rb b/test/test_ssl.rb
index 2e634d71..8b32805e 100644
--- a/test/test_ssl.rb
+++ b/test/test_ssl.rb
@@ -1,5 +1,6 @@
 require File.expand_path('helper', File.dirname(__FILE__))
 require 'webrick/https'
+require 'time'
 
 
 class TestSSL < Test::Unit::TestCase
@@ -87,6 +88,7 @@ def test_verification_without_httpclient
     cert = ::OpenSSL::X509::Certificate.new(raw_cert)
     store = ::OpenSSL::X509::Store.new
     store.add_cert(ca_cert)
+    store.time = Time.new(2017, 01, 01)
     assert(store.verify(cert))
   end