diff --git a/app/mailers/email_reply.rb b/app/mailers/email_reply.rb
index 5c9869a..fac0088 100644
--- a/app/mailers/email_reply.rb
+++ b/app/mailers/email_reply.rb
@@ -8,8 +8,7 @@ class EmailReply < ActionMailer::Base
 
     mail(
       :to => user.email,
-      :subject => "[#{Rails.application.name}] Reply from " <<
-        "#{comment.user.username} on #{comment.story.title}"
+      :subject =>  I18n.t('mailers.email_reply.replysubject', :appname => "#{Rails.application.name}", :author => "#{comment.user.username}", :story => "#{comment.story.title}")
     )
   end
 
@@ -19,8 +18,7 @@ class EmailReply < ActionMailer::Base
 
     mail(
       :to => user.email,
-      :subject => "[#{Rails.application.name}] Mention from " <<
-        "#{comment.user.username} on #{comment.story.title}"
+      :subject =>  I18n.t('mailers.email_reply.mentionsubject', :appname => "#{Rails.application.name}", :author => "#{comment.user.username}", :story => "#{comment.story.title}")
     )
   end
 end
diff --git a/config/locales/en.yml b/config/locales/en.yml
index a06eb50..9d2b0d3 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -6,10 +6,13 @@ en:
     formats:
       default: "%Y-%m-%d %H:%M:%S"
   mailers:
-    invitation_mailer:
-      subject: "[%{appname}] You have been invited to %{appname}"
     email_message:
       subject: "[%{appname}] Private Message from %{author}: %{subject}"
+    email_reply:
+      replysubject: "[%{appname}] Reply from %{author} on %{story}"
+      mentionsubject: "[%{appname}] Mention from %{author} on %{story}"
+    invitation_mailer:
+      subject: "[%{appname}] You have been invited to %{appname}"
   models:
     comment:
       commentcannotbeblank: "A comment cannot be blank."
diff --git a/config/locales/fr.yml b/config/locales/fr.yml
index 1c86167..e78089d 100644
--- a/config/locales/fr.yml
+++ b/config/locales/fr.yml
@@ -18,10 +18,13 @@ fr:
     formats:
       default: "%d-%m-%Y %H:%M:%S"
   mailers:
-    invitation_mailer:
-      subject: "[%{appname}] Vous avez été invité au %{appname}"
     email_message:
       subject: "[%{appname}] Message privé de %{author} : %{subject}"
+    email_reply:
+      replysubject: "[%{appname}] Réponse de %{author} sur %{story}"
+      mentionsubject: "[%{appname}] %{author} vous a mentionné dans %{story}"
+    invitation_mailer:
+      subject: "[%{appname}] Vous avez été invité au %{appname}"
   models:
     comment:
       commentcannotbeblank: "Un commentaire ne peut pas être vide."