scrubyt出现RubyInline (= 3.6.3)错误

在irb中输入
[code]require 'scrubyt'[/code]
出现以下错误信息:
[code]
Gem::Exception: can't activate RubyInline (= 3.6.3), already activated RubyInline-3.6.6]
from /usr/lib/ruby/1.8/rubygems.rb:254:in `activate'
from /usr/lib/ruby/1.8/rubygems.rb:272:in `activate'
from /usr/lib/ruby/1.8/rubygems.rb:271:in `each'
from /usr/lib/ruby/1.8/rubygems.rb:271:in `activate'
from /usr/lib/ruby/1.8/rubygems/custom_require.rb:31:in `require'
from (irb):3
irb(main):004:0> exit

[/code]

解决方法：
输入以下命令：
[code]gem uninstall RubyInline[/code]
出现：
[code]Select gem to uninstall:
1. RubyInline-3.6.3
2. RubyInline-3.6.6
3. All versions[/code]
选择2，回车，这样就删除了3.6.6版本了

不知为什么？当使用[code]gem install scrubyt[/code]安装scrubyt时，总是会把RubyInline的两个版本都安装下去