3 files changed, 9 insertions, 4 deletions
diff --git a/actionpack/lib/action_dispatch/middleware/show_exceptions.rb b/actionpack/lib/action_dispatch/middleware/show_exceptions.rb
index a765c23dae..2fa68c64c5 100644
--- a/actionpack/lib/action_dispatch/middleware/show_exceptions.rb
+++ b/actionpack/lib/action_dispatch/middleware/show_exceptions.rb
@@ -86,8 +86,8 @@ module ActionDispatch
           :framework_trace => framework_trace(exception),
           :full_trace => full_trace(exception)
         )
-        file = "rescues/#{@@rescue_templates[exception.class.name]}.erb"
-        body = template.render(:file => file, :layout => 'rescues/layout.erb')
+        file = "rescues/#{@@rescue_templates[exception.class.name]}"
+        body = template.render(:template => file, :layout => 'rescues/layout')
         render(status_code(exception), body)
       end
 
diff --git a/actionpack/lib/action_view/lookup_context.rb b/actionpack/lib/action_view/lookup_context.rb
index ef1ef44317..fa4bf70f77 100644
--- a/actionpack/lib/action_view/lookup_context.rb
+++ b/actionpack/lib/action_view/lookup_context.rb
@@ -147,7 +147,12 @@ module ActionView
       # as well as incorrectly putting part of the path in the template
       # name instead of the prefix.
       def normalize_name(name, prefixes) #:nodoc:
-        name  = name.to_s.gsub(handlers_regexp, '')
+        name  = name.to_s.sub(handlers_regexp) do |match|
+          ActiveSupport::Deprecation.warn "Passing a template handler in the template name is deprecated. " \
+            "You can simply remove the handler name or pass render :handlers => [:#{match[1..-1]}] instead.", caller
+          ""
+        end
+
         parts = name.split('/')
         name  = parts.pop
 
diff --git a/actionpack/lib/action_view/renderer/abstract_renderer.rb b/actionpack/lib/action_view/renderer/abstract_renderer.rb
index 24bae64ca5..1656cf7ec7 100644
--- a/actionpack/lib/action_view/renderer/abstract_renderer.rb
+++ b/actionpack/lib/action_view/renderer/abstract_renderer.rb
@@ -16,7 +16,7 @@ module ActionView
     def extract_format(value, details)
       if value.is_a?(String) && value.sub!(formats_regexp, "")
         ActiveSupport::Deprecation.warn "Passing the format in the template name is deprecated. " \
-          "Please pass render with :formats => #{$1} instead.", caller
+          "Please pass render with :formats => [:#{$1}] instead.", caller
         details[:formats] ||= [$1.to_sym]
       end
     end