diff --git a/sidekiq_mailer.gemspec b/sidekiq_mailer.gemspec
index 68e571c..487487b 100644
--- a/sidekiq_mailer.gemspec
+++ b/sidekiq_mailer.gemspec
@@ -2,20 +2,20 @@
 require File.expand_path('../lib/sidekiq_mailer/version', __FILE__)
 
 Gem::Specification.new do |gem|
-  gem.authors       = ["Anderson Dias"]
-  gem.email         = ["andersondaraujo@gmail.com"]
-  gem.description   = %q{Asynchronous mail delivery using sidekiq}
-  gem.summary       = %q{Turning ActiveMailer deliveries asynchronous using the power of sidekiq}
-  gem.homepage      = "http://github.com/andersondias/sidekiq_mailer"
+  gem.authors = ["Anderson Dias"]
+  gem.email = ["andersondaraujo@gmail.com"]
+  gem.description = %q{Asynchronous mail delivery using sidekiq}
+  gem.summary = %q{Turning ActiveMailer deliveries asynchronous using the power of sidekiq}
+  gem.homepage = "http://github.com/andersondias/sidekiq_mailer"
 
-  gem.files         = `git ls-files`.split($\)
-  gem.executables   = gem.files.grep(%r{^bin/}).map{ |f| File.basename(f) }
-  gem.test_files    = gem.files.grep(%r{^(test|spec|features)/})
-  gem.name          = "sidekiq_mailer"
+  gem.files = `git ls-files`.split($\)
+  gem.executables = gem.files.grep(%r{^bin/}).map { |f| File.basename(f) }
+  gem.test_files = gem.files.grep(%r{^(test|spec|features)/})
+  gem.name = "sidekiq_mailer"
   gem.require_paths = ["lib"]
-  gem.version       = Sidekiq::Mailer::VERSION
+  gem.version = Sidekiq::Mailer::VERSION
 
-  gem.add_dependency("activesupport", "~> 4.0")
-  gem.add_dependency("actionmailer", "~> 4.0")
+  gem.add_dependency("activesupport", ">= 3.0")
+  gem.add_dependency("actionmailer", ">= 3.0")
   gem.add_dependency("sidekiq", "~> 2.3")
 end