diff --git a/test/data/test2_1-5sec.c b/test/data/test2_1-5sec.c
--- a/test/data/test2_1-5sec.c
+++ b/test/data/test2_1-5sec.c
@@ -11,7 +11,7 @@
   printf("%d\n",a+b);
 
   for(a=0; a<2; a++) {
-    while(c<1150000000) {
+    while(c<1550000000) {
       c++;
       b+=c;
     }
diff --git a/test/engine_spec.rb b/test/engine_spec.rb
--- a/test/engine_spec.rb
+++ b/test/engine_spec.rb
@@ -232,7 +232,7 @@
                     :graded_at= => nil,
                     :compiler_message= => '',
                     :grader_comment= => '',
-                    :running_stat= => /[Ee]xit.*status.*10.*0.0 sec./,
+                    :running_stat= => /[Ee]xit.*status.*10.*0\.0 sec/m,
                     :output_file_name= => lambda { |fname|
                       File.exists?(fname).should be_true
                     },
diff --git a/test/engine_spec_helper.rb b/test/engine_spec_helper.rb
--- a/test/engine_spec_helper.rb
+++ b/test/engine_spec_helper.rb
@@ -9,7 +9,7 @@
   def init_sandbox
     config = Grader::Configuration.get_instance
     clear_sandbox
-    Dir.mkdir config.user_result_dir
+    FileUtils.mkdir_p config.user_result_dir
     cp_cmd = "cp -R #{config.test_data_dir}/ev #{config.test_sandbox_dir}"
     system(cp_cmd)
   end