diff --git a/app/models/grader_message.rb b/app/models/grader_message.rb
deleted file mode 100644
--- a/app/models/grader_message.rb
+++ /dev/null
@@ -1,90 +0,0 @@
-class GraderMessage < ActiveRecord::Base
-
-  belongs_to :taken_grader_process, :class_name => :grader_process
-
-  GRADE_SUBMISSION = 1
-  GRADE_TEST_REQUEST = 2
-  STOP = 3
-
-  RECIPIENT_ANY = -1
-
-  def self.create_message(recipient, command, options=nil, target_id=nil)
-    recipient_id = recipient
-    if recipient == :any
-      recipient_id = GraderMessage::RECIPIENT_ANY
-    end
-    
-    GraderMessage.create(:grader_process_id => recipient_id,
-                         :command => command,
-                         :options => options,
-                         :target_id => target_id,
-                         :taken => false)
-  end
-
-  def self.create_grade_submission(submission, 
-                                   grading_environment="grading")
-    GraderMessage.create_message(:any,
-                                 GraderMessage::GRADE_SUBMISSION,
-                                 grading_environment,
-                                 submission.id)
-  end
-  
-  def self.create_grade_test_request(test_request, 
-                                     grading_environment="grading")
-    GraderMessage.create_message(:any,
-                                 GraderMessage::GRADE_TEST_REQUEST,
-                                 grading_environment,
-                                 test_request.id)
-  end
-  
-  def self.create_stop(grader_process_id)
-    GraderMessage.create_message(grader_process_id,
-                                 GraderMessage::STOP)
-  end
-
-  def self.get_message_for(recipient_id, accepting_commands=:all)
-    command_conditions = 
-      GraderMessage.build_command_conditions(accepting_commands)
-    recp_conditions= "((`grader_process_id` = #{recipient_id.to_i})" +
-      " OR (`grader_process_id` = #{GraderMessage::RECIPIENT_ANY}))"
-
-    message = nil   # need this to bind message in do-block for transaction
-    begin
-      GraderMessage.transaction do
-        message = GraderMessage.find(:first, 
-                                     :order => "created_at", 
-                                     :conditions => 
-                                     "(`taken` = 0)" + 
-                                     " AND (#{recp_conditions})" + 
-                                     " AND (#{command_conditions})",
-                                     :lock => true)
-        if message!=nil
-          message.taken = true
-          message.taken_grader_process_id = recipient_id
-          message.save!
-        end
-      end
-      
-    rescue
-      message = nil
-
-    end
-    
-    message
-  end
-  
-  protected
-  
-  def self.build_command_conditions(accepting_commands)
-    if accepting_commands==:all
-      return '(1=1)'
-    else
-      conds = []
-      accepting_commands.each do |command|
-        conds << "(`command` = #{command.to_i})"
-      end
-      return "(" + conds.join(" OR ") + ")"
-    end
-  end
-  
-end