diff --git a/pymongo/_cbsonmodule.c b/pymongo/_cbsonmodule.c
index b6a45398d..07d7fe78d 100644
--- a/pymongo/_cbsonmodule.c
+++ b/pymongo/_cbsonmodule.c
@@ -1497,11 +1497,10 @@ static PyObject* get_value(const char* buffer, int* position, int type,
         }
     case 17:
         {
-            int time,
-                inc;
+            unsigned int time, inc;
             memcpy(&inc, buffer + *position, 4);
             memcpy(&time, buffer + *position + 4, 4);
-            value = PyObject_CallFunction(Timestamp, "ii", time, inc);
+            value = PyObject_CallFunction(Timestamp, "II", time, inc);
             if (!value) {
                 return NULL;
             }
diff --git a/pymongo/bson.py b/pymongo/bson.py
index 2ab73a05e..35a49a11b 100644
--- a/pymongo/bson.py
+++ b/pymongo/bson.py
@@ -50,9 +50,10 @@ except ImportError:
 RE_TYPE = type(re.compile(""))
 
 
-def _get_int(data, as_class=None):
+def _get_int(data, as_class=None, unsigned=False):
+    format = unsigned and "I" or "i"
     try:
-        value = struct.unpack("<i", data[:4])[0]
+        value = struct.unpack("<%s" % format, data[:4])[0]
     except struct.error:
         raise InvalidBSON()
 
@@ -177,8 +178,8 @@ def _get_ref(data, as_class):
 
 
 def _get_timestamp(data, as_class):
-    (inc, data) = _get_int(data)
-    (timestamp, data) = _get_int(data)
+    (inc, data) = _get_int(data, unsigned=True)
+    (timestamp, data) = _get_int(data, unsigned=True)
     return (Timestamp(timestamp, inc), data)
 
 
@@ -304,8 +305,8 @@ def _element_to_bson(key, value, check_keys):
                      value.microsecond / 1000)
         return "\x09" + name + struct.pack("<q", millis)
     if isinstance(value, Timestamp):
-        time = struct.pack("<i", value.time)
-        inc = struct.pack("<i", value.inc)
+        time = struct.pack("<I", value.time)
+        inc = struct.pack("<I", value.inc)
         return "\x11" + name + inc + time
     if value is None:
         return "\x0A" + name
diff --git a/pymongo/connection.py b/pymongo/connection.py
index 2d8b32bd6..ecf48fd38 100644
--- a/pymongo/connection.py
+++ b/pymongo/connection.py
@@ -450,7 +450,7 @@ class Connection(object): # TODO support auth for pooling
             finally:
                 if sock is not None:
                     sock.close()
-        if sock_error:
+        if sock_error or self.__host is None:
             raise AutoReconnect("could not find master")
         raise ConfigurationError("No master node in %r. You must specify "
                                  "slave_okay to connect to "
diff --git a/pymongo/timestamp.py b/pymongo/timestamp.py
index 6e36f4197..182af8ea9 100644
--- a/pymongo/timestamp.py
+++ b/pymongo/timestamp.py
@@ -56,7 +56,7 @@ class Timestamp(object):
         if not 0 <= time < 2**32:
             raise ValueError("time must be contained in [0, 2**32)")
         if not 0 <= inc < 2**32:
-            raise ValueError("inc must be contained in [0, 2**32)")
+            raise ValueError("inc must be contained in [0, 2**32), not %r" % inc)
 
         self.__time = time
         self.__inc = inc
diff --git a/test/test_database.py b/test/test_database.py
index 86095caf8..0a29b8360 100644
--- a/test/test_database.py
+++ b/test/test_database.py
@@ -198,7 +198,9 @@ class TestDatabase(unittest.TestCase):
         self.assertEqual(prev_error["nPrev"], 1)
         del prev_error["nPrev"]
         prev_error.pop("lastOp", None)
-        self.assertEqual(db.error(), prev_error)
+        error = db.error()
+        error.pop("lastOp", None)
+        self.assertEqual(error, prev_error)
 
         db.test.find_one()
         self.assertEqual(None, db.error())