diff --git a/lib/signature.rb b/lib/signature.rb
index 6e8d283..ea62ba1 100644
--- a/lib/signature.rb
+++ b/lib/signature.rb
@@ -40,7 +40,7 @@ def sign(token)
       @auth_hash = {
         :auth_version => "1.0",
         :auth_key => token.key,
-        :auth_timestamp => Time.now.to_i
+        :auth_timestamp => Time.now.to_i.to_s
       }
 
       @auth_hash[:auth_signature] = signature(token)
diff --git a/spec/signature_spec.rb b/spec/signature_spec.rb
index edce081..09e3899 100644
--- a/spec/signature_spec.rb
+++ b/spec/signature_spec.rb
@@ -31,7 +31,7 @@
       :auth_signature => "da078fcedd72941b6c873caa40d0d6b2000ebfc700cee802b128dd20f72e74e9",
       :auth_version => "1.0",
       :auth_key => "key",
-      :auth_timestamp => 1234
+      :auth_timestamp => '1234'
     }
   end