diff --git a/actionmailer/actionmailer.gemspec b/actionmailer/actionmailer.gemspec
index 9b25feaf756cf..01d97b72132e0 100644
--- a/actionmailer/actionmailer.gemspec
+++ b/actionmailer/actionmailer.gemspec
@@ -22,5 +22,5 @@ Gem::Specification.new do |s|
   s.add_dependency 'actionpack', version
   s.add_dependency 'actionview', version
 
-  s.add_dependency 'mail', '~> 2.5.4'
+  s.add_dependency 'mail', ['~> 2.5', '>= 2.5.4']
 end