namespace problem with iCalendar

i'm developing a calendar webapp for my company using ruby 1.8.7 and
rails 2.3.8.
naturally there are RoR models named "Calendar" and "Event"
in order to send calendar events to other apps (microsoft outlook &
lotus notes) i'm integrating with the iCalendar standard & ruby
library. but this library contains classes called "Calendar" and
"Event"

now my app is getting lotta errors like this when it tries to use
activerecord find - @calendar = Calendar.find(id) :

NoMethodError (undefined method `find' for Icalendar::calendar:Class):
  app/controllers/foos_controller.rb:184:in `sendEmailDialogForm'
  C:/Ruby/lib/ruby/1.8/webrick/httpserver.rb:104:in `service'
  C:/Ruby/lib/ruby/1.8/webrick/httpserver.rb:65:in `run'

is there some way to do @calendar =
ActiveRecord::Base.Calendar.find ?? or something like it...

trying to avoid using a module to specify a namespace or to rename my
models.