diff --git a/lib/tz.py b/lib/tz.py
index e353f9b6..cc99025b 100644
--- a/lib/tz.py
+++ b/lib/tz.py
@@ -38,17 +38,36 @@ class FixedOffsetTimezone(datetime.tzinfo):
     with a small change to the `!__init__()` method to allow for pickling
     and a default name in the form ``sHH:MM`` (``s`` is the sign.).
 
+    The implementation also caches instances. During creation, if a
+    FixedOffsetTimezone instance has previously been created with the same
+    offset and name that instance will be returned. This saves memory and
+    improves comparability.
+
     .. __: http://docs.python.org/library/datetime.html#datetime-tzinfo
     """
     _name = None
     _offset = ZERO
-    
+
+    _cache = {}
+
     def __init__(self, offset=None, name=None):
         if offset is not None:
             self._offset = datetime.timedelta(minutes = offset)
         if name is not None:
             self._name = name
 
+    def __new__(cls, offset=None, name=None):
+        """Return a suitable instance created earlier if it exists
+        """
+        key = (offset, name)
+        try:
+            return cls._cache[key]
+        except KeyError:
+            tz = datetime.tzinfo.__new__(cls, offset, name)
+            tz.__init__(offset, name)
+            cls._cache[key] = tz
+            return tz
+
     def __repr__(self):
         offset_mins = self._offset.seconds // 60 + self._offset.days * 24 * 60
         return "psycopg2.tz.FixedOffsetTimezone(offset=%r, name=%r)" \
diff --git a/tests/test_dates.py b/tests/test_dates.py
index 026561a2..9be68a2c 100755
--- a/tests/test_dates.py
+++ b/tests/test_dates.py
@@ -532,6 +532,13 @@ class FixedOffsetTimezoneTests(unittest.TestCase):
         tzinfo = FixedOffsetTimezone(name="FOO")
         self.assertEqual(repr(tzinfo), "psycopg2.tz.FixedOffsetTimezone(offset=0, name='FOO')")
 
+    def test_instance_caching(self):
+        self.assert_(FixedOffsetTimezone(name="FOO") is FixedOffsetTimezone(name="FOO"))
+        self.assert_(FixedOffsetTimezone(7 * 60) is FixedOffsetTimezone(7 * 60))
+        self.assert_(FixedOffsetTimezone(-9 * 60, 'FOO') is FixedOffsetTimezone(-9 * 60, 'FOO'))
+        self.assert_(FixedOffsetTimezone(9 * 60) is not FixedOffsetTimezone(9 * 60, 'FOO'))
+        self.assert_(FixedOffsetTimezone(name='FOO') is not FixedOffsetTimezone(9 * 60, 'FOO'))
+
 def test_suite():
     return unittest.TestLoader().loadTestsFromName(__name__)