diff --git a/railties/lib/rails/gem_dependency.rb b/railties/lib/rails/gem_dependency.rb
index 9f088a18dd..30bdf416fc 100644
--- a/railties/lib/rails/gem_dependency.rb
+++ b/railties/lib/rails/gem_dependency.rb
@@ -39,7 +39,7 @@ module Rails
       @load_paths_added = true
     rescue Gem::LoadError
     end
-    
+
     def dependencies
       all_dependencies = specification.dependencies.map do |dependency|
         GemDependency.new(dependency.name, :requirement => dependency.version_requirements)
@@ -47,7 +47,7 @@ module Rails
       all_dependencies += all_dependencies.map(&:dependencies).flatten
       all_dependencies.uniq
     end
-    
+
     def gem_dir(base_directory)
       File.join(base_directory, specification.full_name)
     end
@@ -78,13 +78,13 @@ module Rails
       puts cmd
       puts %x(#{cmd})
     end
-    
+
     def unpack_to(directory)
       FileUtils.mkdir_p directory
       Dir.chdir directory do
         Gem::GemRunner.new.run(unpack_command)
       end
-      
+
       # copy the gem's specification into GEMDIR/.specification so that
       # we can access information about the gem on deployment systems
       # without having the gem installed
@@ -103,7 +103,7 @@ private ###################################################################
     def specification
       @spec ||= Gem.source_index.search(Gem::Dependency.new(@name, @requirement)).sort_by { |s| s.version }.last
     end
-    
+
     def gem_command
       RUBY_PLATFORM =~ /win32/ ? 'gem.bat' : 'gem'
     end
@@ -114,11 +114,11 @@ private ###################################################################
       cmd << "--source"  << @source  if @source
       cmd
     end
-    
+
     def unpack_command
       cmd = %w(unpack) << @name
-      cmd << "--version" << "#{@requirement.to_s}" if @requirement
+      cmd << "--version" << %("#{@requirement.to_s}") if @requirement
       cmd
     end
   end
-end
\ No newline at end of file
+end
diff --git a/railties/test/gem_dependency_test.rb b/railties/test/gem_dependency_test.rb
index 3ae0189327..b5946aa7b8 100644
--- a/railties/test/gem_dependency_test.rb
+++ b/railties/test/gem_dependency_test.rb
@@ -10,13 +10,13 @@ uses_mocha "Plugin Tests" do
       @gem              = Rails::GemDependency.new "hpricot"
       @gem_with_source  = Rails::GemDependency.new "hpricot", :source => "http://code.whytheluckystiff.net"
       @gem_with_version = Rails::GemDependency.new "hpricot", :version => "= 0.6"
-      @gem_with_lib     = Rails::GemDependency.new "aws-s3", :lib => "aws/s3" 
+      @gem_with_lib     = Rails::GemDependency.new "aws-s3", :lib => "aws/s3"
     end
 
     def test_configuration_adds_gem_dependency
       config = Rails::Configuration.new
       config.gem "aws-s3", :lib => "aws/s3", :version => "0.4.0"
-      assert_equal [["install", "aws-s3", "--version", "= 0.4.0"]], config.gems.collect(&:install_command)
+      assert_equal [["install", "aws-s3", "--version", '"= 0.4.0"']], config.gems.collect(&:install_command)
     end
 
     def test_gem_creates_install_command
@@ -28,7 +28,7 @@ uses_mocha "Plugin Tests" do
     end
 
     def test_gem_with_version_creates_install_command
-      assert_equal ["install", "hpricot", "--version", "= 0.6"], @gem_with_version.install_command
+      assert_equal ["install", "hpricot", "--version", '"= 0.6"'], @gem_with_version.install_command
     end
 
     def test_gem_creates_unpack_command
@@ -36,26 +36,26 @@ uses_mocha "Plugin Tests" do
     end
 
     def test_gem_with_version_unpack_install_command
-      assert_equal ["unpack", "hpricot", "--version", "= 0.6"], @gem_with_version.unpack_command
+      assert_equal ["unpack", "hpricot", "--version", '"= 0.6"'], @gem_with_version.unpack_command
     end
 
     def test_gem_adds_load_paths
       @gem.expects(:gem).with(@gem.name)
       @gem.add_load_paths
     end
-  
+
     def test_gem_with_version_adds_load_paths
       @gem_with_version.expects(:gem).with(@gem_with_version.name, @gem_with_version.requirement.to_s)
       @gem_with_version.add_load_paths
     end
-  
+
     def test_gem_loading
       @gem.expects(:gem).with(@gem.name)
       @gem.expects(:require).with(@gem.name)
       @gem.add_load_paths
       @gem.load
     end
-  
+
     def test_gem_with_lib_loading
       @gem_with_lib.expects(:gem).with(@gem_with_lib.name)
       @gem_with_lib.expects(:require).with(@gem_with_lib.lib)
@@ -63,4 +63,4 @@ uses_mocha "Plugin Tests" do
       @gem_with_lib.load
     end
   end
-end
\ No newline at end of file
+end