diff --git a/padrino-mailer/lib/padrino-mailer/ext.rb b/padrino-mailer/lib/padrino-mailer/ext.rb
index 9789aa184..23c4c6d52 100644
--- a/padrino-mailer/lib/padrino-mailer/ext.rb
+++ b/padrino-mailer/lib/padrino-mailer/ext.rb
@@ -261,7 +261,7 @@ def render(engine=nil, data=nil, options={}, locals={}, &block)
       engine ||= message_name
 
       if mailer_name && !engine.to_s.index('/')
-        settings.views += "/#{mailer_name}" 
+        settings.views += "/#{mailer_name}" unless settings.views.include?("/#{mailer_name}")
         engine = engine.to_s.sub(%r{^#{mailer_name}/}, '')
       end