diff --git a/ChangeLog b/ChangeLog
index 3b06639623..001e777c7f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+Tue Feb 18 14:24:07 2014  Shota Fukumori  <her@sorah.jp>
+
+	* lib/test/unit/test-unit.gemspec: Add minitest < 5.0.0 dependency
+
+	* tool/rbinstall.rb: Add empty implementations for `add_dependency`,
+	  `add_runtime_dependency`, `add_development_dependency` for
+	  Gem::Specification.
+
 Tue Feb 18 12:06:39 2014  Tanaka Akira  <akr@fsij.org>
 
 	* configure.in (FILE_COUNT): Removed.  (win32.c defines it in itself.)
diff --git a/lib/test/unit/test-unit.gemspec b/lib/test/unit/test-unit.gemspec
index 6c7d22379d..363fd50c02 100644
--- a/lib/test/unit/test-unit.gemspec
+++ b/lib/test/unit/test-unit.gemspec
@@ -11,4 +11,8 @@ Gem::Specification.new do |s|
     "This library implements test/unit compatible API on minitest. " +
     "The test/unit means that test/unit which was bundled with Ruby 1.8."
   s.executables = ["testrb"]
+
+  # Ruby bundled test/unit is a compatibility layer for minitest,
+  # and it doesn't have support for minitest 5.
+  s.add_runtime_dependency "minitest", '< 5.0.0'
 end
diff --git a/tool/rbinstall.rb b/tool/rbinstall.rb
index b3dad0ee89..9207c9f61b 100755
--- a/tool/rbinstall.rb
+++ b/tool/rbinstall.rb
@@ -600,6 +600,15 @@ end
       GEMSPEC
     end
 
+    def add_dependency(*)
+    end
+
+    def add_development_dependency(*)
+    end
+
+    def add_runtime_dependency(*)
+    end
+
     def self.unresolved_deps
       []
     end