diff --git a/zipline/lines.py b/zipline/lines.py
index 9a0b49ef..9bc8b3ac 100644
--- a/zipline/lines.py
+++ b/zipline/lines.py
@@ -62,7 +62,7 @@ before invoking simulate.
 import sys
 import zmq
 import os
-from signal import SIGHUP
+from signal import SIGHUP, SIGINT
 import multiprocessing
 from setproctitle import setproctitle
 
@@ -118,6 +118,9 @@ class SimulatedTrading(object):
         self.logger = Logger(sim_id)
         self.print_logger = Logger('Print')
 
+        # exit status flag
+        self.success = False
+
 
     def simulate(self, blocking=True, send_sighup=False):
 
@@ -155,28 +158,28 @@ class SimulatedTrading(object):
                 self.results_socket.send(msg)
 
             self.signal_done()
+            self.success = True
         except Exception as exc:
             self.handle_exception(exc)
         finally:
+            # not much to do besides log our exit.
             self.close()
 
     def signal_done(self):
         # notify monitor we're done
-        done_frame = zp.DONE_FRAME('succes')
+        done_frame = zp.DONE_FRAME('success')
         self.results_socket.send(done_frame)
 
     def close(self):
         log.info("Closing Simulation: {id}".format(id=self.sim_id))
         if self.proc and self.send_sighup:
             ppid = os.getppid()
-            log.warning("Sending SIGHUP")
-            os.kill(ppid, SIGHUP)
-
-    def cancel(self):
-        if self.proc and self.proc.is_alive():
-            self.proc.terminate()
-        else:
-            self.gen.throw(CancelSignal())
+            if self.success:
+                log.warning("Sending SIGHUP")
+                os.kill(ppid, SIGHUP)
+            else:
+                log.warning("Sending SIGINT")
+                os.kill(ppid, SIGINT)
 
     def handle_exception(self, exc):
         if isinstance(exc, CancelSignal):
diff --git a/zipline/protocol.py b/zipline/protocol.py
index b5bf67ae..dd46bd60 100644
--- a/zipline/protocol.py
+++ b/zipline/protocol.py
@@ -527,11 +527,15 @@ def EXCEPTION_FRAME(exception_tb, name, message):
     rlist = []
     for stack in stack_list:
         filename = shorten_filename(stack[0])
+        # default the line to empty string rather than None
+        line = ''
+        if stack[3]:
+            line = stack[3]
         rstack = {
             'filename'  : filename,
             'lineno'    : stack[1],
             'method'    : stack[2],
-            'line'      : stack[3]
+            'line'      : line
         }
         rlist.append(rstack)
     result = {
diff --git a/zipline/utils/test_utils.py b/zipline/utils/test_utils.py
index 02ac4c69..13924f60 100644
--- a/zipline/utils/test_utils.py
+++ b/zipline/utils/test_utils.py
@@ -4,6 +4,7 @@ import time
 import zipline.protocol as zp
 from datetime import datetime
 import blist
+from bson import ObjectId
 from zipline.utils.date_utils import EPOCH
 from itertools import izip
 from logbook import FileHandler
@@ -31,6 +32,7 @@ def check_dict(test, a, b, label):
         # ignore the extra fields used by dictshield
         if key in ['progress']:
             continue
+
         test.assertTrue(a.has_key(key), "missing key at: " + label + "." + key)
         test.assertTrue(b.has_key(key), "missing key at: " + label + "." + key)
         a_val = a[key]
@@ -60,6 +62,13 @@ def check(test, a, b, label=None):
     else:
         test.assertEqual(a, b, "mismatch on path: " + label)
 
+def check_excluded(test, a, excluded_keys=[]):
+    for key, value in a.iteritems():
+        test.assertTrue(key not in excluded_keys)
+        test.assertFalse(key.endswith('_id'), 'Avoid _id fields!')
+        test.assertFalse(isinstance(value, ObjectId))
+        if isinstance(value, dict):
+            check_excluded(test, value, excluded_keys)
 
 def drain_zipline(test, zipline, p_blocking=False):
     assert test.ctx, "method expects a valid zmq context"