Conflict the key name in MongoMapper

I use mongo mapper (0.8.6) in my sinatra service. I have one problem with stack level too deep. The problem is that there is conflict of the key "changes" in my model. Here is my model:

class ChangeLog
  include MongoMapper::Document

  belongs_to :resource

  key :changes, Hash, :required => true
  key :message, String, :required => true
  key :note, String
  key :user_uuid, String, :required => true
  key :user_name, String, :required => true
  timestamps!
end

However, I don't want开发者_运维技巧 to rename my key as in this case, it's the right name for my web service. Any suggestions?

---

changes is an instance method that will tell you what fields have changed since you last saved the document. Here's an example from MongoMapper's documentation

user = User.create(:name => 'John', :age => 29)

puts user.changed?        # false
puts user.changes.inspect # {}

user.name = 'Steve'
puts user.changed?            # true
puts user.changes.inspect     # {"name"=>["John", "Steve"]}

Unfortunately, you're probably going to need to choose a different name for that field. Maybe "adjustments" or "variations" or "differences" or "modifications"?