deploy@39:~$ gem install rubygems-update
Successfully installed rubygems-update-2.0.0
Parsing documentation for rubygems-update-2.0.0
Done installing documentation for rubygems-update (0 sec).
1 gem installed
deploy@39:~$ update_rubygems
RubyGems 2.0.0 installed
Parsing documentation for rubygems-2.0.0
Installing ri documentation for rubygems-2.0.0

ERROR:  While executing gem ... (ArgumentError)
    invalid byte sequence in US-ASCII

好像是字符什么出错的，但是不知道为什么修改，google 找了都没有发现有人遇见过这样情况。。