diff --git a/lib/rubygems.rb b/lib/rubygems.rb
index 29552d9..814c4f4 100644
--- a/lib/rubygems.rb
+++ b/lib/rubygems.rb
@@ -299,7 +299,7 @@ module Gem

   def self.bindir(install_dir=Gem.dir)
     return File.join install_dir, "bin" unless
-      install_dir.to_s == Gem.default_dir.to_s
+      install_dir.to_s == Gem.default_system_dir.to_s
     Gem.default_bindir
   end

diff --git a/lib/rubygems/defaults.rb b/lib/rubygems/defaults.rb
index 8e0182f..aa53e4c 100644
--- a/lib/rubygems/defaults.rb
+++ b/lib/rubygems/defaults.rb
@@ -31,6 +31,10 @@ module Gem
     @default_dir ||= File.join(RbConfig::CONFIG["rubylibprefix"], "gems", RbConfig::CONFIG["ruby_version"])
   end

+  def self.default_system_dir
+    File.join("/usr/local/lib/ruby/gems", RbConfig::CONFIG["ruby_version"])
+  end
+
   ##
   # Returns binary extensions dir for specified RubyGems base dir or nil
   # if such directory cannot be determined.
diff --git a/lib/rubygems/path_support.rb b/lib/rubygems/path_support.rb
index d601e65..0c78dba 100644
--- a/lib/rubygems/path_support.rb
+++ b/lib/rubygems/path_support.rb
@@ -23,7 +23,7 @@ class Gem::PathSupport
   # hashtable, or defaults to ENV, the system environment.
   #
   def initialize(env)
-    @home = env["GEM_HOME"] || Gem.default_dir
+    @home = env["GEM_HOME"] || Gem.default_system_dir

     if File::ALT_SEPARATOR
       @home = @home.gsub(File::ALT_SEPARATOR, File::SEPARATOR)