(Rails on Ruby)错误“NameError (undefined local variable or method `acts_as_taggab”

我已经在InstantRails 2.0安装了acts_as_taggable-2.0.2.gem
在模型Bookmark.rb中用到“acts_as_taggable”，出现“500 internal error”.谢谢各位帮忙！
####################################################################################
Bookmark.rb代码片断如下：
class Bookmark < ActiveRecord::Base
# A bookmark can have tags. The relationships between bookmarks and
# tags are managed by the acts_as_taggable plugin.
acts_as_taggable
####################################################################################
log记录如下：
NameError (undefined local variable or method acts_as_taggable' for #<Class:0x4a9f048>):
C:/InstantRails-2.0-win/ruby/lib/ruby/gems/1.8/gems/activerecord-2.0.2/lib/active_record/base.rb:1532:inmethod_missing'
/app/models/bookmark.rb:7
C:/InstantRails-2.0-win/ruby/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:203:in load_without_new_constant_marking'
C:/InstantRails-2.0-win/ruby/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:203:inload_file'
C:/InstantRails-2.0-win/ruby/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:342:in new_constants_in'
C:/InstantRails-2.0-win/ruby/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:202:inload_file'
C:/InstantRails-2.0-win/ruby/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:94:in require_or_load'
C:/InstantRails-2.0-win/ruby/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:248:inload_missing_constant'
C:/InstantRails-2.0-win/ruby/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:453:in const_missing'
C:/InstantRails-2.0-win/ruby/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:465:inconst_missing'
C:/InstantRails-2.0-win/ruby/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:471:in send'
C:/InstantRails-2.0-win/ruby/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:471:inconst_missing'
/app/controllers/bookmarks_controller.rb:24:in `create'
[b]问题补充：[/b]
“在WIN的话 请直接使用 gem install acts_as_taggable
如果还不行
那就去github 下一份acts_as_taggable到PLUGIN 就能正常使用了
记得 要重新执行一次ruby script/server”
上面的方法我都试过了，还是同样的错误。

这个需要一个tags表，你可以用这个插件试试，里面有 readme

[url]http://github.com/mattetti/acts_as_taggable_on_steroids/[/url]

在WIN的话 请直接使用 gem install acts_as_taggable
如果还不行
那就去github 下一份acts_as_taggable到PLUGIN 就能正常使用了
记得 要重新执行一次ruby script/server

反正是没有加载成功=.=