diff --git a/lib/core/settings.py b/lib/core/settings.py
index fdf25a0e5..45098f417 100644
--- a/lib/core/settings.py
+++ b/lib/core/settings.py
@@ -18,7 +18,7 @@ from lib.core.enums import OS
 from thirdparty.six import unichr as _unichr
 
 # sqlmap version (<major>.<minor>.<month>.<monthly commit>)
-VERSION = "1.4.1.39"
+VERSION = "1.4.1.40"
 TYPE = "dev" if VERSION.count('.') > 2 and VERSION.split('.')[-1] != '0' else "stable"
 TYPE_COLORS = {"dev": 33, "stable": 90, "pip": 34}
 VERSION_STRING = "sqlmap/%s#%s" % ('.'.join(VERSION.split('.')[:-1]) if VERSION.count('.') > 2 and VERSION.split('.')[-1] == '0' else VERSION, TYPE)
diff --git a/lib/request/dns.py b/lib/request/dns.py
index 352de63d2..ec1ac1e6c 100644
--- a/lib/request/dns.py
+++ b/lib/request/dns.py
@@ -17,13 +17,6 @@ import time
 
 class DNSQuery(object):
     """
-    Used for making fake DNS resolution responses based on received
-    raw request
-
-    Reference(s):
-        http://code.activestate.com/recipes/491264-mini-fake-dns-server/
-        https://code.google.com/p/marlon-tools/source/browse/tools/dnsproxy/dnsproxy.py
-
     >>> DNSQuery(b'|K\\x01 \\x00\\x01\\x00\\x00\\x00\\x00\\x00\\x01\\x03www\\x06google\\x03com\\x00\\x00\\x01\\x00\\x01\\x00\\x00)\\x10\\x00\\x00\\x00\\x00\\x00\\x00\\x0c\\x00\\n\\x00\\x08O4|Np!\\x1d\\xb3')._query == b"www.google.com."
     True
     """
@@ -32,9 +25,9 @@ class DNSQuery(object):
         self._raw = raw
         self._query = b""
 
-        type_ = (ord(raw[2:3]) >> 3) & 15                 # Opcode bits
+        type_ = (ord(raw[2:3]) >> 3) & 15                   # Opcode bits
 
-        if type_ == 0:                                  # Standard query
+        if type_ == 0:                                      # Standard query
             i = 12
             j = ord(raw[i:i + 1])
 
@@ -65,6 +58,15 @@ class DNSQuery(object):
         return retVal
 
 class DNSServer(object):
+    """
+    Used for making fake DNS resolution responses based on received
+    raw request
+
+    Reference(s):
+        http://code.activestate.com/recipes/491264-mini-fake-dns-server/
+        https://code.google.com/p/marlon-tools/source/browse/tools/dnsproxy/dnsproxy.py
+    """
+
     def __init__(self):
         self._check_localhost()
         self._requests = []
@@ -99,9 +101,15 @@ class DNSServer(object):
 
         retVal = None
 
+        if prefix and hasattr(prefix, "encode"):
+            prefix = prefix.encode()
+
+        if suffix and hasattr(suffix, "encode"):
+            suffix = suffix.encode()
+
         with self._lock:
             for _ in self._requests:
-                if prefix is None and suffix is None or re.search(r"%s\..+\.%s" % (prefix, suffix), _, re.I):
+                if prefix is None and suffix is None or re.search(b"%s\..+\.%s" % (prefix, suffix), _, re.I):
                     retVal = _
                     self._requests.remove(_)
                     break