diff --git a/server/filter.py b/server/filter.py
index 45963d0e..8d2b38f6 100644
--- a/server/filter.py
+++ b/server/filter.py
@@ -354,6 +354,9 @@ class Filter(JailThread):
 		self.__setFilePos()
 		lastLine = None
 		for line in self.__crtHandler:
+			if not self.isActive():
+				# The jail has been stopped
+				break
 			try:
 				# Decode line to UTF-8
 				line = line.decode('utf-8')
diff --git a/testcases/filtertestcase.py b/testcases/filtertestcase.py
index d51892a5..91c5a592 100644
--- a/testcases/filtertestcase.py
+++ b/testcases/filtertestcase.py
@@ -24,7 +24,7 @@ __date__ = "$Date$"
 __copyright__ = "Copyright (c) 2004 Cyril Jaquier"
 __license__ = "GPL"
 
-import unittest, socket
+import unittest
 from server.filterpoll import FilterPoll
 from server.filter import Filter
 from server.failmanager import FailManager
@@ -87,6 +87,8 @@ class GetFailures(unittest.TestCase):
 	def setUp(self):
 		"""Call before every test case."""
 		self.__filter = Filter(None)
+		self.__filter.setActive(True)
+		# TODO Test this
 		#self.__filter.setTimeRegex("\S{3}\s{1,2}\d{1,2} \d{2}:\d{2}:\d{2}")
 		#self.__filter.setTimePattern("%b %d %H:%M:%S")