diff --git a/lib/sinatra/base.rb b/lib/sinatra/base.rb
index ab759865..2098cf5d 100644
--- a/lib/sinatra/base.rb
+++ b/lib/sinatra/base.rb
@@ -727,7 +727,7 @@ module Sinatra
       res = catch(:halt) { yield }
       res = [res] if Fixnum === res or String === res
       if Array === res and Fixnum === res.first
-        raise TypeError, "#{res.inspect} not supported" if res.length > 3
+        raise ArgumentError, "#{res.inspect} not supported" if res.length > 3
         status(res.shift)
         body(res.pop)
         headers(*res)
diff --git a/test/result_test.rb b/test/result_test.rb
index eb574c9b..22827f32 100644
--- a/test/result_test.rb
+++ b/test/result_test.rb
@@ -76,14 +76,14 @@ class ResultTest < Test::Unit::TestCase
     assert_equal 'formula of', body
   end
 
-  it "raises a TypeError when result is a non two or three tuple Array" do
+  it "raises a ArgumentError when result is a non two or three tuple Array" do
     mock_app {
       get '/' do
         [409, 'formula of', 'something else', 'even more']
       end
     }
 
-    assert_raise(TypeError) { get '/' }
+    assert_raise(ArgumentError) { get '/' }
   end
 
   it "sets status when result is a Fixnum status code" do