diff --git a/environment.rb.SAMPLE b/environment.rb.SAMPLE
--- a/environment.rb.SAMPLE
+++ b/environment.rb.SAMPLE
@@ -3,4 +3,4 @@
 RAILS_APP_DIR = "/home/jittat/web_grader"
 
 # load the required environment file
-require "env_#{GRADER_ENV}.rb"
+require File.dirname(__FILE__) + "/env_#{GRADER_ENV}.rb"
diff --git a/grader b/grader
--- a/grader
+++ b/grader
@@ -86,7 +86,7 @@
 if ARGV.length > 1
   GRADER_ENV = ARGV[1]
 end
-require "environment.rb"
+require File.dirname(__FILE__) + "/environment.rb"
 
 #main program
 
diff --git a/import_problem b/import_problem
--- a/import_problem
+++ b/import_problem
@@ -35,7 +35,7 @@
   end
 end
 
-GRADER_DIR = "/home/jittat/grader/grader_ng"
+GRADER_DIR = File.dirname(__FILE__)
 
 # print usage
 if ARGV.length < 3