Overriding parts of acts_as_taggable

Hello,

I would like to override parts of acts_as_taggable plugin. In particular I would like to override some of the functions in tag.rb and acts_as_taggable.rb. What is the best way to go about doing this. I put something like this in RAILS_ROOT/lib/acts_as_taggable_helper.rb, which is a file I created:

class Tag   def my_method      # do some stuff here...   end end

But it didn't work. What is the best way to go about doing this without altering the original files.

TIA.