God , Resque, Resque-schedule, is working,but buggy. Need to combine with LDAP and also implement XML calendar sync.

Rakefile

@@ -1,7 +1,9 @@
+# /usr/bin/ruby -Ku
 # Add your own tasks in files placed in lib/tasks ending in .rake,
 # for example lib/tasks/capistrano.rake, and they will automatically be available to Rake.
 
 require File.expand_path('../config/application', __FILE__)
+require 'resque/tasks'
 require 'rake/dsl_definition'
 require 'rake'