3 files changed, 3 insertions, 3 deletions
diff --git a/actionmailer/lib/action_mailer/base.rb b/actionmailer/lib/action_mailer/base.rb
index fcdd6747b8..cc3a412221 100644
--- a/actionmailer/lib/action_mailer/base.rb
+++ b/actionmailer/lib/action_mailer/base.rb
@@ -685,7 +685,7 @@ module ActionMailer
       # Call all the procs (if any)
       class_default = self.class.default
       default_values = class_default.merge(class_default) do |k,v|
-        v.respond_to?(:to_proc) ? instance_eval(&v) : v
+        v.is_a?(Proc) ? instance_eval(&v) : v
       end
 
       # Handle defaults
diff --git a/actionmailer/lib/action_mailer/delivery_methods.rb b/actionmailer/lib/action_mailer/delivery_methods.rb
index 9a1a27c8ed..aedcd81e52 100644
--- a/actionmailer/lib/action_mailer/delivery_methods.rb
+++ b/actionmailer/lib/action_mailer/delivery_methods.rb
@@ -64,7 +64,7 @@ module ActionMailer
           raise "Delivery method cannot be nil"
         when Symbol
           if klass = delivery_methods[method]
-            mail.delivery_method(klass,(send(:"#{method}_settings") || {}).merge!(options || {}))
+            mail.delivery_method(klass, (send(:"#{method}_settings") || {}).merge(options || {}))
           else
             raise "Invalid delivery method #{method.inspect}"
           end
diff --git a/actionmailer/lib/action_mailer/mail_helper.rb b/actionmailer/lib/action_mailer/mail_helper.rb
index 8d6e082d02..54ad9f066f 100644
--- a/actionmailer/lib/action_mailer/mail_helper.rb
+++ b/actionmailer/lib/action_mailer/mail_helper.rb
@@ -50,7 +50,7 @@ module ActionMailer
       end
 
       indentation = " " * indent
-      sentences.map { |sentence|
+      sentences.map! { |sentence|
         "#{indentation}#{sentence.join(' ')}"
       }.join "\n"
     end