Ruby on rails Rails机架冲突

在OSX上安装ruby和rails后，我遇到了机架冲突错误

sudo rails new test -T
/Library/Ruby/Site/1.8/rubygems/specification.rb:1990:in `raise_if_conflicts': Unable to activate actionpack-3.2.13, because rack-1.5.2 conflicts with rack (~> 1.4.5) (Gem::LoadError)
    from /Library/Ruby/Site/1.8/rubygems/specification.rb:1163:in `activate'
    from /Library/Ruby/Site/1.8/rubygems/specification.rb:1199:in `activate_dependencies'
    from /Library/Ruby/Site/1.8/rubygems/specification.rb:1185:in `each'
    from /Library/Ruby/Site/1.8/rubygems/specification.rb:1185:in `activate_dependencies'
    from /Library/Ruby/Site/1.8/rubygems/specification.rb:1167:in `activate'
    from /Library/Ruby/Site/1.8/rubygems/core_ext/kernel_gem.rb:48:in `gem'
    from /usr/bin/rails:18

请试试这个：

gem卸载机架

Select gem to uninstall:
1. rack-1.4.5
2. rack-1.5.2
3. All versions 
>2
Successfully uninstalled rack-1.5.2

请试试这个：

gem卸载机架

Select gem to uninstall:
1. rack-1.4.5
2. rack-1.5.2
3. All versions 
>2
Successfully uninstalled rack-1.5.2

---

我现在不再安装任何版本的rack。如何安装版本1.4.5？***本地GEMS***机架缓存（1.2）机架ssl（1.3.3）机架测试（0.6.2）请使用：--gem安装机架-v 1.4.5工作！！谢谢，那么最新的机架版本是怎么回事？！我现在不再安装任何版本的rack。如何安装版本1.4.5？***本地GEMS***机架缓存（1.2）机架ssl（1.3.3）机架测试（0.6.2）请使用：--gem安装机架-v 1.4.5工作！！谢谢，那么最新的机架版本是怎么回事？！