Index: Objects/descrobject.c
===================================================================
--- Objects/descrobject.c	(revision 72178)
+++ Objects/descrobject.c	(working copy)
@@ -1233,25 +1233,19 @@
 	}
 	if (doc == NULL || doc == Py_None) {
 		Py_XDECREF(doc);
-		doc = pold->prop_doc ? pold->prop_doc : Py_None;
+		if (pold->getter_doc && get != Py_None) {
+			/* make _init use __doc__ from getter */
+			doc = Py_None;
+		}
+		else {
+			doc = pold->prop_doc ? pold->prop_doc : Py_None;
+		}
 	}
-	
+
 	new =  PyObject_CallFunction(type, "OOOO", get, set, del, doc);
 	Py_DECREF(type);
 	if (new == NULL)
 		return NULL;
-	pnew = (propertyobject *)new;
-	
-	if (pold->getter_doc && get != Py_None) {
-		PyObject *get_doc = PyObject_GetAttrString(get, "__doc__");
-		if (get_doc != NULL) {
-			Py_XDECREF(pnew->prop_doc);
-			pnew->prop_doc = get_doc;  /* get_doc already INCREF'd by GetAttr */
-			pnew->getter_doc = 1;
-		} else {
-			PyErr_Clear();
-		}
-	}
 	return new;
 }
 
@@ -1288,8 +1282,20 @@
 	if ((doc == NULL || doc == Py_None) && get != NULL) {
 		PyObject *get_doc = PyObject_GetAttrString(get, "__doc__");
 		if (get_doc != NULL) {
-			Py_XDECREF(prop->prop_doc);
-			prop->prop_doc = get_doc;  /* get_doc already INCREF'd by GetAttr */
+			/* get_doc already INCREF'd by GetAttr */
+			if (Py_TYPE(self)==&PyProperty_Type) {
+				Py_XDECREF(prop->prop_doc);
+				prop->prop_doc = get_doc;
+			} else {
+				/* Put __doc__ in dict of the subclass instance instead,
+				otherwise it gets shadowed by class's __doc__. */
+				if (PyObject_SetAttrString(self, "__doc__", get_doc) != 0)
+				{
+					/* DECREF for props handled by _dealloc */
+					Py_DECREF(get_doc);
+					return -1;
+	                        }
+			}
 			prop->getter_doc = 1;
 		} else {
 			PyErr_Clear();
Index: Lib/test/test_property.py
===================================================================
--- Lib/test/test_property.py	(revision 72149)
+++ Lib/test/test_property.py	(working copy)
@@ -91,8 +91,62 @@
         self.assertEqual(base.__class__.spam.__doc__, "spam spam spam")
         self.assertEqual(sub.__class__.spam.__doc__, "spam spam spam")
 
+
+# Issue 5890: subclasses of property do not preserve method __doc__ strings
+class PropertySub(property):
+    """This is a subclass of property"""
+
+class PSBaseClass(object):
+    @PropertySub
+    def spam(self):
+        """spam wrapped in a property subclass"""
+        return 1
+
+class PropertySubSlots(property):
+    """This is a subclass of property that defines __slots__"""
+    __slots__ = ()
+
+class PSBaseClassWithSetter(object):
+    @PropertySub
+    def spam(self):
+        """a docstring"""
+        return 1
+    @spam.setter
+    def setspam(self, value):
+        """set spam, badly"""
+        x = foo
+
+
+class PropertySubclassTests(unittest.TestCase):
+
+    def test_docstring(self):
+        base = PSBaseClass()
+        self.assertEqual(
+            base.__class__.spam.__doc__,
+            "spam wrapped in a property subclass")
+
+    def test_slotsdocstringexception(self):
+        try:
+            class Foo(object):
+                @PropertySubSlots
+                def spam(self):
+                    """Trying to copy this docstring will raise an exception"""
+                    return 1
+        except AttributeError:
+            pass
+        else:
+            raise Exception("AttributeError not raised")
+
+    def test_property_copy_on_subclass(self):
+        base = PSBaseClassWithSetter()
+        self.assertEqual(
+            base.__class__.spam.__doc__,
+            "a docstring")
+
+
+
 def test_main():
-    run_unittest(PropertyTests)
+    run_unittest(PropertyTests, PropertySubclassTests)
 
 if __name__ == '__main__':
     test_main()