diff --git a/lib/multipass.rb b/lib/multipass.rb
index 54a33c6..ac9f0fa 100644
--- a/lib/multipass.rb
+++ b/lib/multipass.rb
@@ -99,8 +99,8 @@ def decode(data)
 
   CipherError = OpenSSL.const_defined?(:CipherError) ? OpenSSL::CipherError : OpenSSL::Cipher::CipherError
 
-  if Object.const_defined?(:ActiveSupport)
-    include ActiveSupport::Base64
+  if defined?(::ActiveSupport) && defined?(::ActiveSupport::Base64)
+    include ::ActiveSupport::Base64
   else
     require 'base64'
   end
@@ -145,7 +145,7 @@ def self.decode_64(s, url_safe = true)
   if Object.const_defined?(:ActiveSupport)
     def decode_json(data, s)
       ActiveSupport::JSON.decode(s)
-    rescue ActiveSupport::JSON::ParseError
+    rescue ActiveSupport::JSON.parse_error
       raise MultiPass::JSONError.new(data, s)
     end
   else