diff --git a/lib/capybara/selector.rb b/lib/capybara/selector.rb
index f56fa532..1c572034 100644
--- a/lib/capybara/selector.rb
+++ b/lib/capybara/selector.rb
@@ -381,3 +381,11 @@ Capybara.add_selector(:table) do
     xpath
   end
 end
+
+Capybara.add_selector(:frame) do
+  xpath do |locator|
+    xpath = XPath.descendant(:iframe)
+    xpath = xpath[XPath.attr(:id).equals(locator.to_s) | XPath.attr(:name).equals(locator)] unless locator.nil?
+    xpath
+  end
+end
\ No newline at end of file
diff --git a/lib/capybara/session.rb b/lib/capybara/session.rb
index 9a5cbbd7..1f06d5d2 100644
--- a/lib/capybara/session.rb
+++ b/lib/capybara/session.rb
@@ -345,9 +345,9 @@ module Capybara
       when Capybara::Node::Element
         locator
       when String
-        find(:xpath, XPath.descendant(:iframe)[XPath.attr(:id).equals(locator) | XPath.attr(:name).equals(locator)].to_xpath(:exact))
+        find(:frame, locator)
       when Integer
-        all(:css, 'iframe', minimum: locator+1)[locator]
+        all(:frame, minimum: locator+1)[locator]
       else
         raise ArgumentError
       end