diff --git a/common/lib/capa/capa/util.py b/common/lib/capa/capa/util.py
index 211ada4d62..98c250297d 100644
--- a/common/lib/capa/capa/util.py
+++ b/common/lib/capa/capa/util.py
@@ -39,10 +39,18 @@ def convert_files_to_filenames(answers):
     '''
     new_answers = dict()
     for answer_id in answers.keys():
-        # TODO This should be done more cleanly; however, this fixes bugs
-        # that were introduced with this function.
-        if isinstance(answers[answer_id], list):
-            new_answers[answer_id] = answers[answer_id]
+        if is_uploaded_file(answers[answer_id]):
+            new_answers[answer_id] = answers[answer_id].name
         else:
-            new_answers[answer_id] = unicode(answers[answer_id])
+            new_answers[answer_id] = answers[answer_id]
     return new_answers
+
+def is_uploaded_file(file_to_test):
+    '''
+    Duck typing to check if 'file_to_test' is a File object
+    '''
+    is_file = True
+    for method in ['read', 'name']:
+        if not hasattr(file_to_test, method):
+            is_file = False
+    return is_file 
diff --git a/common/lib/xmodule/xmodule/tests/__init__.py b/common/lib/xmodule/xmodule/tests/__init__.py
index 7b1641956c..4c0b6fc9b3 100644
--- a/common/lib/xmodule/xmodule/tests/__init__.py
+++ b/common/lib/xmodule/xmodule/tests/__init__.py
@@ -15,6 +15,7 @@ import xmodule
 import capa.calc as calc
 import capa.capa_problem as lcp
 from capa.correctmap import CorrectMap
+from capa.util import convert_files_to_filenames
 from xmodule import graders, x_module
 from xmodule.x_module import ModuleSystem
 from xmodule.graders import Score, aggregate_scores
@@ -31,7 +32,7 @@ i4xs = ModuleSystem(
     user=Mock(),
     filestore=fs.osfs.OSFS(os.path.dirname(os.path.realpath(__file__))),
     debug=True,
-    xqueue=None, # TODO FIXME
+    xqueue=None,
     is_staff=False
 )
 
@@ -278,7 +279,6 @@ class StringResponseWithHintTest(unittest.TestCase):
 class CodeResponseTest(unittest.TestCase):
     '''
     Test CodeResponse
-
     '''
     def test_update_score(self):
         problem_file = os.path.dirname(__file__) + "/test_files/coderesponse.xml"
@@ -327,7 +327,18 @@ class CodeResponseTest(unittest.TestCase):
                         self.assertFalse(test_lcp.correct_map.is_queued(answer_ids[j]))  # Should be dequeued, message delivered
                     else:
                         self.assertTrue(test_lcp.correct_map.is_queued(answer_ids[j]))  # Should be queued, message undelivered
-
+    
+    def test_convert_files_to_filenames(self):
+        problem_file = os.path.dirname(__file__) + "/test_files/coderesponse.xml"
+        fp = open(problem_file)
+        answers_with_file = {'1_2_1': 'String-based answer',
+                             '1_3_1': ['answer1', 'answer2', 'answer3'],
+                             '1_4_1': fp}
+        answers_converted = convert_files_to_filenames(answers_with_file)
+        self.assertEquals(answers_converted['1_2_1'], 'String-based answer')
+        self.assertEquals(answers_converted['1_3_1'], ['answer1', 'answer2', 'answer3'])
+        self.assertEquals(answers_converted['1_4_1'], fp.name)
+        
 
 class ChoiceResponseTest(unittest.TestCase):
 
diff --git a/common/lib/xmodule/xmodule/x_module.py b/common/lib/xmodule/xmodule/x_module.py
index f013aac785..9b005d1dae 100644
--- a/common/lib/xmodule/xmodule/x_module.py
+++ b/common/lib/xmodule/xmodule/x_module.py
@@ -643,7 +643,7 @@ class ModuleSystem(object):
                  user=None,
                  filestore=None,
                  debug=False,
-                 xqueue = None,
+                 xqueue=None,
                  is_staff=False):
         '''
         Create a closure around the system environment.
@@ -678,7 +678,10 @@ class ModuleSystem(object):
              TODO (vshnayder): this will need to change once we have real user roles.
         '''
         self.ajax_url = ajax_url
-        self.xqueue = xqueue
+        if xqueue is None:
+            self.xqueue = {'interface':None, 'callback_url':'/', 'default_queuename':'null'}
+        else:
+            self.xqueue = xqueue
         self.track_function = track_function
         self.filestore = filestore
         self.get_module = get_module