Index: Lib/decimal.py
===================================================================
--- Lib/decimal.py	(revision 59809)
+++ Lib/decimal.py	(working copy)
@@ -135,6 +135,7 @@
 ]
 
 import copy as _copy
+import numbers
 
 # Rounding
 ROUND_DOWN = 'ROUND_DOWN'
@@ -527,7 +528,7 @@
         # and the Decimal constructor still deal with tuples of
         # digits.
 
-        self = object.__new__(cls)
+        self = super(Decimal, cls).__new__(cls)
 
         # From a string
         # REs insist on real strings, so we can too.
@@ -761,11 +762,6 @@
             return NotImplemented
         return self.__cmp__(other) == 0
 
-    def __ne__(self, other):
-        if not isinstance(other, (Decimal, int, long)):
-            return NotImplemented
-        return self.__cmp__(other) != 0
-
     def compare(self, other, context=None):
         """Compares one to another.
 
@@ -881,6 +877,20 @@
         """
         return self.__str__(eng=True, context=context)
 
+    @property
+    def real(self):
+        """The real component of a Decimal is itself."""
+        return +self
+
+    @property
+    def imag(self):
+        """The imaginary component of a Decimal is 0."""
+        return Decimal(0)
+
+    def conjugate(self):
+        """The complex conjugate of a Decimal is itself."""
+        return +self
+
     def __neg__(self, context=None):
         """Returns a copy with the sign switched.
 
@@ -1405,6 +1415,10 @@
 
     def __int__(self):
         """Converts self to an int, truncating if necessary."""
+        return int(self.__trunc__())
+
+    def __trunc__(self):
+        """Truncates self to an int or long."""
         if self._is_special:
             if self._isnan():
                 context = getcontext()
@@ -1420,9 +1434,9 @@
     def __long__(self):
         """Converts to a long.
 
-        Equivalent to long(int(self))
+        Equivalent to long(trunc(self))
         """
-        return long(self.__int__())
+        return long(self.__trunc__())
 
     def _fix_nan(self, context):
         """Decapitate the payload of a NaN to fit the context"""
@@ -3328,6 +3342,9 @@
             return self     # My components are also immutable
         return self.__class__(str(self))
 
+numbers.Real.register(Decimal)
+numbers.Inexact.register(Decimal)
+
 def _dec_from_triple(sign, coefficient, exponent, special=False):
     """Create a decimal instance directly, without any validation,
     normalization (e.g. removal of leading zeros) or argument
@@ -3336,7 +3353,7 @@
     This function is for *internal use only*.
     """
 
-    self = object.__new__(Decimal)
+    self = super(Decimal, Decimal).__new__(Decimal)
     self._sign = sign
     self._int = coefficient
     self._exp = exponent
Index: Lib/numbers.py
===================================================================
--- Lib/numbers.py	(revision 59809)
+++ Lib/numbers.py	(working copy)
@@ -45,7 +45,6 @@
 
 Inexact.register(complex)
 Inexact.register(float)
-# Inexact.register(decimal.Decimal)
 
 
 class Complex(Number):
@@ -257,7 +256,6 @@
         return +self
 
 Real.register(float)
-# Real.register(decimal.Decimal)
 
 
 class Rational(Real, Exact):
Index: Lib/test/test_decimal.py
===================================================================
--- Lib/test/test_decimal.py	(revision 59809)
+++ Lib/test/test_decimal.py	(working copy)
@@ -27,6 +27,7 @@
 
 import unittest
 import glob
+import numbers
 import os, sys
 import pickle, copy
 from decimal import *
@@ -829,7 +830,15 @@
         self.assertEqual(-Decimal(45), Decimal(-45))           #  -
         self.assertEqual(abs(Decimal(45)), abs(Decimal(-45)))  # abs
 
+    def test_trunc(self):
+        self.assertEqual(int, type(trunc(Decimal("17.5"))))
+        self.assertEqual(17, trunc(Decimal("17")))
+        self.assertEqual(17, trunc(Decimal("17.0001")))
+        self.assertEqual(17, trunc(Decimal("17.999999")))
+        self.assertEqual(-17, trunc(Decimal("-17.999999")))
+        self.assertEqual(10**30, trunc(Decimal("1e30")))
 
+
 # The following are two functions used to test threading in the next class
 
 def thfunc1(cls):
@@ -1172,7 +1181,13 @@
         d = d1.max(d2)
         self.assertTrue(type(d) is Decimal)
 
+    def test_base_classes(self):
+        self.assertTrue(issubclass(Decimal, numbers.Real))
+        self.assertTrue(issubclass(Decimal, numbers.Inexact))
+        self.assertFalse(issubclass(Decimal, numbers.Rational))
+        self.assertFalse(issubclass(Decimal, numbers.Exact))
 
+
 class DecimalPythonAPItests(unittest.TestCase):
 
     def test_pickle(self):
@@ -1191,6 +1206,17 @@
             r = d.to_integral(ROUND_DOWN)
             self.assertEqual(Decimal(int(d)), r)
 
+    def assertTypedEquals(self, a, b):
+        self.assertEquals(type(a), type(b))
+        self.assertEquals(a, b)
+
+    def test_Complex(self):
+        """Check the implementation of numbers.Complex."""
+        d = Decimal("-3.14")
+        self.assertTypedEquals(d, d.real)
+        self.assertTypedEquals(Decimal(0), d.imag)
+        self.assertTypedEquals(d, d.conjugate())
+
 class ContextAPItests(unittest.TestCase):
 
     def test_pickle(self):