diff --git a/fail2ban/tests/actiontestcase.py b/fail2ban/tests/actiontestcase.py
index a4b453a3..1cba0bcc 100644
--- a/fail2ban/tests/actiontestcase.py
+++ b/fail2ban/tests/actiontestcase.py
@@ -200,10 +200,10 @@ class CommandActionTest(LogCaptureTestCase):
 			RuntimeError, CommandAction.executeCmd, 'sleep 60', timeout=2)
 		# give a test still 1 second, because system could be too busy
 		self.assertTrue(time.time() >= stime + 2 and time.time() <= stime + 3)
-		self.assertLogged({
+		self.assertLogged(
 			'sleep 60 -- timed out after 2 seconds',
 			'sleep 60 -- timed out after 3 seconds'
-		})
+		)
 		self.assertLogged('sleep 60 -- killed with SIGTERM')
 
 	def testExecuteTimeoutWithNastyChildren(self):
diff --git a/fail2ban/tests/utils.py b/fail2ban/tests/utils.py
index 9d50646a..35fa59fd 100644
--- a/fail2ban/tests/utils.py
+++ b/fail2ban/tests/utils.py
@@ -232,8 +232,8 @@ class LogCaptureTestCase(unittest.TestCase):
 	def _is_logged(self, s):
 		return s in self._log.getvalue()
 
-	def assertLogged(self, s):
-		"""Assert that a string was logged
+	def assertLogged(self, *s):
+		"""Assert that one of the strings was logged
 
 		Preferable to assertTrue(self._is_logged(..)))
 		since provides message with the actual log.
@@ -244,28 +244,25 @@ class LogCaptureTestCase(unittest.TestCase):
 		  Test should succeed if string (or any of the listed) is present in the log
 		"""
 		logged = self._log.getvalue()
-
-		s_iter = s if isinstance(s, (tuple, list, set)) else [s]
-		for s_ in s_iter:
+		for s_ in s:
 			if s_ in logged:
 				return
-		raise AssertionError("%r was not found in the log: %r" % (s, logged))
+		raise AssertionError("None among %r was found in the log: %r" % (s, logged))
 
-	def assertNotLogged(self, s):
-		"""Assert that a string was not logged
+	def assertNotLogged(self, *s):
+		"""Assert that strings were not logged
 
 		Parameters
 		----------
 		s : string or list/set/tuple of strings
-		  Test should succeed if the string (or at least one of the listed) is not present in the log
+		  Test should succeed if the string (or at least one of the listed) is not
+		  present in the log
 		"""
 		logged = self._log.getvalue()
-
-		s_iter = s if isinstance(s, (tuple, list, set)) else [s]
-		for s_ in s_iter:
+		for s_ in s:
 			if s_ not in logged:
 				return
-		raise AssertionError("%r was found present in the log: %r" % (s, logged))
+		raise AssertionError("All of the %r were found present in the log: %r" % (s, logged))
 
 
 	def getLog(self):