diff --git a/Gemfile.lock b/Gemfile.lock
index e6f7b56..1c3de1c 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -2,37 +2,54 @@ PATH
   remote: .
   specs:
     image_bundle (0.0.2)
-      actionpack (~> 3.0.7)
+      actionpack (>= 3.0.7, < 7.1.0)
 
 GEM
   remote: http://rubygems.org/
   specs:
-    abstract (1.0.0)
-    actionpack (3.0.7)
-      activemodel (= 3.0.7)
-      activesupport (= 3.0.7)
-      builder (~> 2.1.2)
-      erubis (~> 2.6.6)
-      i18n (~> 0.5.0)
-      rack (~> 1.2.1)
-      rack-mount (~> 0.6.14)
-      rack-test (~> 0.5.7)
-      tzinfo (~> 0.3.23)
-    activemodel (3.0.7)
-      activesupport (= 3.0.7)
-      builder (~> 2.1.2)
-      i18n (~> 0.5.0)
-    activesupport (3.0.7)
-    builder (2.1.2)
-    erubis (2.6.6)
-      abstract (>= 1.0.0)
-    i18n (0.5.0)
-    rack (1.2.3)
-    rack-mount (0.6.14)
-      rack (>= 1.0.0)
-    rack-test (0.5.7)
-      rack (>= 1.0)
-    tzinfo (0.3.27)
+    actionpack (7.0.4.2)
+      actionview (= 7.0.4.2)
+      activesupport (= 7.0.4.2)
+      rack (~> 2.0, >= 2.2.0)
+      rack-test (>= 0.6.3)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.0, >= 1.2.0)
+    actionview (7.0.4.2)
+      activesupport (= 7.0.4.2)
+      builder (~> 3.1)
+      erubi (~> 1.4)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.1, >= 1.2.0)
+    activesupport (7.0.4.2)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 1.6, < 2)
+      minitest (>= 5.1)
+      tzinfo (~> 2.0)
+    builder (3.2.4)
+    concurrent-ruby (1.2.0)
+    crass (1.0.6)
+    erubi (1.12.0)
+    i18n (1.12.0)
+      concurrent-ruby (~> 1.0)
+    loofah (2.19.1)
+      crass (~> 1.0.2)
+      nokogiri (>= 1.5.9)
+    mini_portile2 (2.8.1)
+    minitest (5.17.0)
+    nokogiri (1.14.0)
+      mini_portile2 (~> 2.8.0)
+      racc (~> 1.4)
+    racc (1.6.2)
+    rack (2.2.6.2)
+    rack-test (2.0.2)
+      rack (>= 1.3)
+    rails-dom-testing (2.0.3)
+      activesupport (>= 4.2.0)
+      nokogiri (>= 1.6)
+    rails-html-sanitizer (1.5.0)
+      loofah (~> 2.19, >= 2.19.1)
+    tzinfo (2.0.5)
+      concurrent-ruby (~> 1.0)
 
 PLATFORMS
   ruby
diff --git a/image_bundle.gemspec b/image_bundle.gemspec
index 791d050..f69aa14 100644
--- a/image_bundle.gemspec
+++ b/image_bundle.gemspec
@@ -14,7 +14,7 @@ Gem::Specification.new do |s|
   s.license     = "LGPL-2"
 
   s.rubyforge_project = "image_bundle"
-  s.add_dependency "actionpack", "~> 3.0.7"
+  s.add_dependency "actionpack", ">= 3.0.7", "< 7.1.0"
 
   s.files         = `git ls-files`.split("\n")
   s.test_files    = `git ls-files -- {test,spec,features}/*`.split("\n")