diff --git a/ChangeLog b/ChangeLog
index 1bb0e209f5..5d65c8de13 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Fri Feb  1 23:04:00 2013  Charlie Somerville  <charlie@charliesomerville.com>
+
+	* array.c (rb_ary_dup): make returned array the same class as the original
+	  array [Bug #7768] [ruby-core:51792]
+	* test/ruby/test_array.rb (class TestArray): add test
+
 Fri Feb  1 16:35:34 2013  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* marshal.c (r_object0): prohibit setting instance variables of
diff --git a/array.c b/array.c
index a7c74a2aa4..b4216ac1d0 100644
--- a/array.c
+++ b/array.c
@@ -1778,7 +1778,8 @@ rb_ary_empty_p(VALUE ary)
 VALUE
 rb_ary_dup(VALUE ary)
 {
-    VALUE dup = rb_ary_new2(RARRAY_LEN(ary));
+    VALUE ary_class = rb_obj_class(ary);
+    VALUE dup = ary_new(ary_class ? ary_class : rb_cArray, RARRAY_LEN(ary));
     MEMCPY(RARRAY_PTR(dup), RARRAY_PTR(ary), VALUE, RARRAY_LEN(ary));
     ARY_SET_LEN(dup, RARRAY_LEN(ary));
     return dup;
diff --git a/test/ruby/test_array.rb b/test/ruby/test_array.rb
index 3ab0895f8c..c231ecccd1 100644
--- a/test/ruby/test_array.rb
+++ b/test/ruby/test_array.rb
@@ -2283,4 +2283,11 @@ class TestArray < Test::Unit::TestCase
 
     assert_include([4, 7], a.bsearch {|x| (2**100).coerce((1 - x / 4) * (2**100)).first })
   end
+
+  def test_array_uniq_returns_same_class # [ruby-core:51792]
+    klass = Class.new(Array)
+    assert_equal klass, klass.new(2).uniq.class
+    assert_equal klass, klass.new(1).uniq.class
+    assert_equal klass, klass.new(0).uniq.class
+  end
 end