diff -r 937b4376e4b7 Lib/test/test_functools.py
--- a/Lib/test/test_functools.py	Sat Mar 31 13:39:42 2012 -0700
+++ b/Lib/test/test_functools.py	Sat Mar 31 20:59:36 2012 -0600
@@ -144,6 +144,15 @@
         join = self.thetype(''.join)
         self.assertEqual(join(data), '0123456789')
 
+    def test_attribute_assignment(self):
+        f = self.thetype(int, base=2)
+        doc = 'Convert base 2 string to an int.'
+        f.__doc__ = doc
+        self.assertEqual(f.__doc__, doc)
+        val = 'bar'
+        f.foo = val
+        self.assertEqual(f.foo, val)
+
 class PartialSubclass(functools.partial):
     pass
 
diff -r 937b4376e4b7 src/org/python/modules/_functools/PyPartial.java
--- a/src/org/python/modules/_functools/PyPartial.java	Sat Mar 31 13:39:42 2012 -0700
+++ b/src/org/python/modules/_functools/PyPartial.java	Sat Mar 31 20:59:36 2012 -0600
@@ -10,6 +10,7 @@
 import org.python.core.PyStringMap;
 import org.python.core.PyTuple;
 import org.python.core.PyType;
+import org.python.expose.ExposedDelete;
 import org.python.expose.ExposedGet;
 import org.python.expose.ExposedMethod;
 import org.python.expose.ExposedNew;
@@ -122,6 +123,16 @@
         return func.__call__(argAppl, kwAppl);
     }
 
+    @ExposedSet(name = "func")
+    public void setFunc(PyObject value) {
+        throw Py.TypeError("readonly attribute");
+    }
+
+    @ExposedDelete(name = "func")
+    public void delFunc() {
+        throw Py.TypeError("readonly attribute");
+    }
+
     @ExposedGet(name = "args")
     public PyObject getArgs() {
         PyObject[] justArgs;
@@ -135,6 +146,16 @@
         return new PyTuple(justArgs);
     }
 
+    @ExposedSet(name = "args")
+    public void setArgs(PyObject value) {
+        throw Py.TypeError("readonly attribute");
+    }
+
+    @ExposedDelete(name = "args")
+    public void delArgs() {
+        throw Py.TypeError("readonly attribute");
+    }
+
     @ExposedGet(name = "keywords")
     public PyObject getKeywords() {
         if (keywords.length == 0) {
@@ -148,6 +169,22 @@
         return kwDict;
     }
 
+    @ExposedSet(name = "keywords")
+    public void setKeywords(PyObject value) {
+        throw Py.TypeError("readonly attribute");
+    }
+
+    @ExposedDelete(name = "keywords")
+    public void delKeywords() {
+        throw Py.TypeError("readonly attribute");
+    }
+
+    @Override
+    public PyObject fastGetDict() {
+        ensureDict();
+        return __dict__;
+    }
+
     @Override
     @ExposedGet(name = "__dict__")
     public PyObject getDict() {
@@ -164,6 +201,12 @@
         __dict__ = val;
     }
 
+    @Override
+    @ExposedDelete(name = "__dict__")
+    public void delDict() {
+        throw Py.TypeError("a partial object's dictionary may not be deleted");
+    }
+
     private void ensureDict() {
         if (__dict__ == null) {
             __dict__ = new PyStringMap();