diff --git a/fail2ban/server/ipdns.py b/fail2ban/server/ipdns.py
index 880e3f30..8109c21a 100644
--- a/fail2ban/server/ipdns.py
+++ b/fail2ban/server/ipdns.py
@@ -171,7 +171,7 @@ class IPAddr(object):
 		# IP address without CIDR mask
 		if len(s) > 2:
 			raise ValueError("invalid ipstr %r, too many plen representation" % (ipstr,))
-		if "." in s[1]: # 255.255.255.0 style mask
+		if "." in s[1] or ":" in s[1]: # 255.255.255.0 resp. ffff:: style mask
 			s[1] = IPAddr.masktoplen(s[1])
 		s[1] = long(s[1])
 		return s
@@ -235,7 +235,7 @@ class IPAddr(object):
 		return self.ntoa
 
 	def __reduce__(self):
-		"""IPAddr pickle-handler, that simple wrap IPAddr to the str
+		"""IPAddr pickle-handler, that simply wraps IPAddr to the str
 
 		Returns a string as instance to be pickled, because fail2ban-client can't
 		unserialize IPAddr objects
@@ -392,17 +392,29 @@ class IPAddr(object):
 		
 		return (self.addr & mask) == net.addr
 
+	# Pre-calculated map: addr to maskplen
+	def __getMaskMap():
+		m6 = (1 << 128)-1
+		m4 = (1 << 32)-1
+		mmap = {m6: 128, m4: 32, 0: 0}
+		m = 0
+		for i in xrange(0, 128):
+			m |= 1 << i
+			if i < 32:
+				mmap[m ^ m4] = 32-1-i
+			mmap[m ^ m6] = 128-1-i
+		return mmap
+
+	MAP_ADDR2MASKPLEN = __getMaskMap()
+
 	@property
 	def maskplen(self):
 		mplen = 0
 		if self._maskplen is not None:
 			return self._maskplen
-		maddr = self._addr
-		while maddr:
-			if not (maddr & 0x80000000):
-				raise ValueError("invalid mask %r, no plen representation" % (str(self),))
-			maddr = (maddr << 1) & 0xFFFFFFFFL
-			mplen += 1
+		mplen = IPAddr.MAP_ADDR2MASKPLEN.get(self._addr)
+		if mplen is None:
+			raise ValueError("invalid mask %r, no plen representation" % (str(self),))
 		self._maskplen = mplen
 		return mplen
 		
diff --git a/fail2ban/tests/filtertestcase.py b/fail2ban/tests/filtertestcase.py
index 5e493f83..1d4db3a2 100644
--- a/fail2ban/tests/filtertestcase.py
+++ b/fail2ban/tests/filtertestcase.py
@@ -1452,11 +1452,24 @@ class DNSUtilsNetworkTests(unittest.TestCase):
 		self.assertEqual(IPAddr('93.184.0.1', 24).ntoa, '93.184.0.0/24')
 		self.assertEqual(IPAddr('192.168.1.0/255.255.255.128').ntoa, '192.168.1.0/25')
 
+		self.assertEqual(IPAddr('93.184.0.1/32').ntoa, '93.184.0.1')
+		self.assertEqual(IPAddr('93.184.0.1/255.255.255.255').ntoa, '93.184.0.1')
+
 		self.assertEqual(str(IPAddr('2606:2800:220:1:248:1893:25c8::', 120)), '2606:2800:220:1:248:1893:25c8:0/120')
 		self.assertEqual(IPAddr('2606:2800:220:1:248:1893:25c8::', 120).ntoa, '2606:2800:220:1:248:1893:25c8:0/120')
 		self.assertEqual(str(IPAddr('2606:2800:220:1:248:1893:25c8:0/120')), '2606:2800:220:1:248:1893:25c8:0/120')
 		self.assertEqual(IPAddr('2606:2800:220:1:248:1893:25c8:0/120').ntoa, '2606:2800:220:1:248:1893:25c8:0/120')
 
+		self.assertEqual(str(IPAddr('2606:28ff:220:1:248:1893:25c8::', 25)), '2606:2880::/25')
+		self.assertEqual(str(IPAddr('2606:28ff:220:1:248:1893:25c8::/ffff:ff80::')), '2606:2880::/25')
+		self.assertEqual(str(IPAddr('2606:28ff:220:1:248:1893:25c8::/ffff:ffff:ffff:ffff:ffff:ffff:ffff::')), 
+			'2606:28ff:220:1:248:1893:25c8:0/112')
+
+		self.assertEqual(str(IPAddr('2606:28ff:220:1:248:1893:25c8::/128')), 
+			'2606:28ff:220:1:248:1893:25c8:0')
+		self.assertEqual(str(IPAddr('2606:28ff:220:1:248:1893:25c8::/ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff')), 
+			'2606:28ff:220:1:248:1893:25c8:0')
+
 	def testIPAddr_CIDR_Repr(self):
 		self.assertEqual(["127.0.0.0/8", "::/32", "2001:db8::/32"],
 			[IPAddr("127.0.0.0", 8), IPAddr("::1", 32), IPAddr("2001:db8::", 32)]
diff --git a/fail2ban/tests/servertestcase.py b/fail2ban/tests/servertestcase.py
index 90f7aaf2..b79a5652 100644
--- a/fail2ban/tests/servertestcase.py
+++ b/fail2ban/tests/servertestcase.py
@@ -1021,7 +1021,11 @@ class ServerConfigReaderTests(LogCaptureTestCase):
 						cmd[2] = 'polling'
 					# change log path to test log of jail (to prevent "Permission denied" on /var/logs/ for test-user):
 					elif len(cmd) > 3 and cmd[0] == 'set' and cmd[2] == 'addlogpath':
-						cmd[3] = os.path.join(TEST_FILES_DIR, 'logs', cmd[1])
+						fn = os.path.join(TEST_FILES_DIR, 'logs', cmd[1])
+						# fallback to testcase01 if jail has not an own test log-file (currently should be no matter):
+						if not os.path.exists(fn): # pragma: no cover
+							fn = os.path.join(TEST_FILES_DIR, 'testcase01.log')
+						cmd[3] = fn
 					# if fast add dummy regex to prevent too long compile of all regexp (we don't use it in this test at all):
 					elif unittest.F2B.fast and (
 						len(cmd) > 3 and cmd[0] in ('set', 'multi-set') and cmd[2] == 'addfailregex'