diff --git a/lib/bundler/source/git.rb b/lib/bundler/source/git.rb
index 0ee9e4d..234392d 100644
--- a/lib/bundler/source/git.rb
+++ b/lib/bundler/source/git.rb
@@ -187,7 +187,6 @@ module Bundler
       rescue PathError => e
         Bundler.ui.trace e
         raise GitError, "#{to_s} is not yet checked out. Run `bundle install` first."
-		git_proxy.checkout
       end
 
       # This is the path which is going to contain a cache
diff --git a/lib/bundler/source/git/git_proxy.rb b/lib/bundler/source/git/git_proxy.rb
index ec72fcb..67618fc 100644
--- a/lib/bundler/source/git/git_proxy.rb
+++ b/lib/bundler/source/git/git_proxy.rb
@@ -75,36 +75,49 @@ module Bundler
 				Bundler.ui.confirm "Updating #{uri}"
 				FileUtils.cd(path)
 				git_retry %|fetch --force --quiet --tags #{uri_escaped} "refs/heads/*:refs/heads/*"|
-				@commit_num = `git log  -1 --pretty=format:"%H"`[0..11]
-				@new_path = path.dirname
-				@old_folder_name = path.basename.to_s + '/'
-				@fold_name =''
-				@fold_name = path.basename.to_s
-				@fold_name = @fold_name.split('-')[0..-2].join('-')
-				@new_path += (@fold_name + '-' + @commit_num)
-				path = @new_path
-				FileUtils.cd('..')
-				FileUtils.mv( @old_folder_name , path.basename.to_s+'/') if (Dir.exist? (path.basename.to_s+'/')) == false
-				FileUtils.cd(@new_path.to_s)
-				@path_destination = Pathname.new(path.dirname)
-				@path_destination= @path_destination.parent.parent.parent + Pathname.new("bundler/gems/#{path.basename}")
-				if (Dir.exist?(@path_destination.to_s)) == false
-					begin
-						FileUtils.cd(@path_destination.dirname)
-					rescue 
-						FileUtils.mkdir_p(@path_destination.dirname)
-						FileUtils.cd(@path_destination.dirname)
+				if path.to_s.include?("cache")
+					@commit_num = `git log  -1 --pretty=format:"%H"`[0..11] if revision.nil?
+					@commit_num = revision[0..11] if !revision.nil?
+					@new_path = path.dirname
+					@old_folder_name = path.basename.to_s + '/'
+					@fold_name =''
+					@fold_name = path.basename.to_s
+					@fold_name = @fold_name.split('-')[0..-2].join('-')
+					@new_path += (@fold_name + '-' + @commit_num)
+					path = @new_path
+					FileUtils.cd('..')
+					FileUtils.mv( @old_folder_name , path.basename.to_s+'/') if ( Dir.exist?(path.basename.to_s+'/')) == false
+					FileUtils.rmdir @old_folder_name.to_s if ( Dir.exist?(@old_folder_name.to_s+'/') && (@old_folder_name.to_s != path.basename.to_s))
+					FileUtils.cd(@new_path.to_s)
+					@path_destination = Pathname.new(path.dirname)
+					@path_destination= @path_destination.parent.parent.parent + Pathname.new("bundler/gems/#{path.basename}")
+					if (Dir.exist?(@path_destination.to_s)) == false
+						begin
+							FileUtils.cd(@path_destination.dirname)
+						rescue
+							FileUtils.mkdir_p(@path_destination.dirname)
+							FileUtils.cd(@path_destination.dirname)
+						end
+						FileUtils.mkdir(@path_destination.basename)
+						`cp -r "#{path}"/. "#{@path_destination}"/.git/`
+						FileUtils.cd(@path_destination.basename)
+						`git init`
+						`git checkout "#{ref}"`
+					end
+					@gemspec_name = ''
+					FileUtils.cd(@path_destination.to_s)
+					`ls`.split.each{|name| (@gemspec_name = name.to_s and break) if (name.include? '.gemspec') == true}
+					Dir.chdir(Bundler.root.to_s) do
+						Bundler::load_gemspec("#{@path_destination}/#{@gemspec_name}") rescue puts "you don't have .gemspec file at #{@path_destination}"
+					end
+				else
+					@gemspec_name = ''
+					FileUtils.cd(path.to_s)
+					`ls`.split.each{|name| (@gemspec_name = name.to_s and break) if (name.include? '.gemspec') == true}
+					Dir.chdir(Bundler.root.to_s) do
+						Bundler::load_gemspec("#{path}/#{@gemspec_name}") rescue puts "you don't have .gemspec file at #{path}"
 					end
-					FileUtils.mkdir(@path_destination.basename)
-					`cp -r "#{path}"/. "#{@path_destination}"/.git/`
-					FileUtils.cd(@path_destination.basename)
-					`git init`
-					`git checkout "#{ref}"`
 				end
-				@gemspec_name = ''
-				FileUtils.cd(@path_destination.to_s)
-				`ls`.split.each{|name| (@gemspec_name = name.to_s and break) if (name.include? '.gemspec') == true}
-				Bundler::load_gemspec("#{@path_destination}/#{@gemspec_name}") rescue puts "you don't have .gemspec file at #{@path_destination}"
 				FileUtils.cd(@old_pwd)
 			end
           else
@@ -112,38 +125,55 @@ module Bundler
 			if path != nil
 				FileUtils.mkdir_p(path.dirname)
 				git_retry %|clone #{uri_escaped} "#{path}" --bare --no-hardlinks --quiet|
-				FileUtils.cd(path)
-				git_retry %|fetch --all|
-				@commit_num = `git log  -1 --pretty=format:"%H"`[0..11]
-				@new_path = path.dirname
-				@old_folder_name = path.basename.to_s + '/'
-				@fold_name =''
-				@fold_name = path.basename.to_s
-				@fold_name = @fold_name.split('-')[0..-2].join('-')
-				@new_path += (@fold_name + '-' + @commit_num)
-				path = @new_path
-				FileUtils.cd('..')
-				FileUtils.mv( @old_folder_name , path.basename.to_s+'/') if (Dir.exist? (path.basename.to_s+'/')) == false
-				FileUtils.cd(@new_path.to_s)
-				@path_destination = Pathname.new(path.dirname)
-				@path_destination= @path_destination.parent.parent.parent + Pathname.new("bundler/gems/#{path.basename}")
-				if (Dir.exist?(@path_destination.to_s)) == false
-					begin
-						FileUtils.cd(@path_destination.dirname)
-					rescue 
-						FileUtils.mkdir_p(@path_destination.dirname)
-						FileUtils.cd(@path_destination.dirname)
+				if path.to_s.include?("cache")
+					FileUtils.cd(path)
+					git_retry %|fetch --all|
+					@commit_num = `git log  -1 --pretty=format:"%H"`[0..11] if revision.nil?
+					@commit_num = revision[0..11] if !revision.nil?
+					@new_path = path.dirname
+					@old_folder_name = path.basename.to_s + '/'
+					@fold_name =''
+					@fold_name = path.basename.to_s
+					@fold_name = @fold_name.split('-')[0..-2].join('-')
+					@new_path += (@fold_name + '-' + @commit_num)
+					path = @new_path
+					FileUtils.cd('..')
+					FileUtils.mv( @old_folder_name , path.basename.to_s+'/') if (Dir.exist? (path.basename.to_s+'/')) == false
+					FileUtils.rmdir @old_folder_name.to_s if ( Dir.exist?(@old_folder_name.to_s+'/') && (@old_folder_name.to_s != path.basename.to_s))
+					FileUtils.cd(@new_path.to_s)
+					@path_destination = Pathname.new(path.dirname)
+					@path_destination= @path_destination.parent.parent.parent + Pathname.new("bundler/gems/#{path.basename}")
+					if (Dir.exist?(@path_destination.to_s)) == false
+						begin
+							FileUtils.cd(@path_destination.dirname)
+						rescue
+							FileUtils.mkdir_p(@path_destination.dirname)
+							FileUtils.cd(@path_destination.dirname)
+						end
+						FileUtils.mkdir(@path_destination.basename)
+						`cp -r "#{path}"/. "#{@path_destination}"/.git/`
+						FileUtils.cd(@path_destination.basename)
+						`git init`
+						`git checkout "#{ref}"`
+					end
+					@gemspec_name = ''
+					FileUtils.cd(@path_destination.to_s)
+					`ls`.split.each{|name| (@gemspec_name = name.to_s and break) if (name.include? '.gemspec') == true}
+					@EXT_LOCK.synchronize do
+						Dir.chdir(Bundler.root.to_s) do
+							Bundler::load_gemspec("#{@path_destination}/#{@gemspec_name}") rescue puts "you don't have .gemspec file at #{@path_destination}"
+						end
+					end
+				else
+					@gemspec_name = ''
+					FileUtils.cd(path.to_s)
+					`ls`.split.each{|name| (@gemspec_name = name.to_s and break) if (name.include? '.gemspec') == true}
+					@EXT_LOCK.synchronize do
+						Dir.chdir(Bundler.root.to_s) do
+							Bundler::load_gemspec("#{path}/#{@gemspec_name}") rescue puts "you don't have .gemspec file at #{path}"
+						end
 					end
-					FileUtils.mkdir(@path_destination.basename)
-					`cp -r "#{path}"/. "#{@path_destination}"/.git/`
-					FileUtils.cd(@path_destination.basename)
-					`git init`
-					`git checkout "#{ref}"`
 				end
-				@gemspec_name = ''
-				FileUtils.cd(@path_destination.to_s)
-				`ls`.split.each{|name| (@gemspec_name = name.to_s and break) if (name.include? '.gemspec') == true}
-				Bundler::load_gemspec("#{@path_destination}/#{@gemspec_name}") rescue puts "you don't have .gemspec file at #{@path_destination}"
 			end
           end
 		  FileUtils.cd(@org_pwd)