diff --git a/django/newforms/widgets.py b/django/newforms/widgets.py
index f701faa35d..d50b1921ea 100644
--- a/django/newforms/widgets.py
+++ b/django/newforms/widgets.py
@@ -260,8 +260,8 @@ class RadioSelect(Select):
         "Returns a RadioFieldRenderer instance rather than a Unicode string."
         if value is None: value = ''
         str_value = smart_unicode(value) # Normalize to string.
-        attrs = attrs or {}
-        return RadioFieldRenderer(name, str_value, attrs, list(chain(self.choices, choices)))
+        final_attrs = self.build_attrs(attrs)
+        return RadioFieldRenderer(name, str_value, final_attrs, list(chain(self.choices, choices)))
 
     def id_for_label(self, id_):
         # RadioSelect is represented by multiple <input type="radio"> fields,
@@ -327,14 +327,25 @@ class MultiWidget(Widget):
         if not isinstance(value, list):
             value = self.decompress(value)
         output = []
+        final_attrs = self.build_attrs(attrs)
+        id_ = final_attrs.get('id', None)
         for i, widget in enumerate(self.widgets):
             try:
                 widget_value = value[i]
-            except KeyError:
+            except IndexError:
                 widget_value = None
-            output.append(widget.render(name + '_%s' % i, widget_value, attrs))
+            if id_:
+                final_attrs = dict(final_attrs, id='%s_%s' % (id_, i))
+            output.append(widget.render(name + '_%s' % i, widget_value, final_attrs))
         return self.format_output(output)
 
+    def id_for_label(self, id_):
+        # See the comment for RadioSelect.id_for_label()
+        if id_:
+            id_ += '_0'
+        return id_
+    id_for_label = classmethod(id_for_label)
+
     def value_from_datadict(self, data, name):
         return [data.get(name + '_%s' % i) for i in range(len(self.widgets))]
 
diff --git a/tests/regressiontests/forms/tests.py b/tests/regressiontests/forms/tests.py
index 4521d17d7f..8f8b3c828a 100644
--- a/tests/regressiontests/forms/tests.py
+++ b/tests/regressiontests/forms/tests.py
@@ -658,10 +658,31 @@ Traceback (most recent call last):
 ...
 IndexError: list index out of range
 
+# Unicode choices are correctly rendered as HTML
 >>> w = RadioSelect()
 >>> unicode(w.render('email', 'ŠĐĆŽćžšđ', choices=[('ŠĐĆŽćžšđ', 'ŠĐabcĆŽćžšđ'), ('ćžšđ', 'abcćžšđ')]))
 u'<ul>\n<li><label><input checked="checked" type="radio" name="email" value="\u0160\u0110\u0106\u017d\u0107\u017e\u0161\u0111" /> \u0160\u0110abc\u0106\u017d\u0107\u017e\u0161\u0111</label></li>\n<li><label><input type="radio" name="email" value="\u0107\u017e\u0161\u0111" /> abc\u0107\u017e\u0161\u0111</label></li>\n</ul>'
 
+# Attributes provided at instantiation are passed to the constituent inputs
+>>> w = RadioSelect(attrs={'id':'foo'})
+>>> print w.render('beatle', 'J', choices=(('J', 'John'), ('P', 'Paul'), ('G', 'George'), ('R', 'Ringo')))
+<ul>
+<li><label><input checked="checked" type="radio" id="foo_0" value="J" name="beatle" /> John</label></li>
+<li><label><input type="radio" id="foo_1" value="P" name="beatle" /> Paul</label></li>
+<li><label><input type="radio" id="foo_2" value="G" name="beatle" /> George</label></li>
+<li><label><input type="radio" id="foo_3" value="R" name="beatle" /> Ringo</label></li>
+</ul>
+
+# Attributes provided at render-time are passed to the constituent inputs
+>>> w = RadioSelect()
+>>> print w.render('beatle', 'J', choices=(('J', 'John'), ('P', 'Paul'), ('G', 'George'), ('R', 'Ringo')), attrs={'id':'bar'})
+<ul>
+<li><label><input checked="checked" type="radio" id="bar_0" value="J" name="beatle" /> John</label></li>
+<li><label><input type="radio" id="bar_1" value="P" name="beatle" /> Paul</label></li>
+<li><label><input type="radio" id="bar_2" value="G" name="beatle" /> George</label></li>
+<li><label><input type="radio" id="bar_3" value="R" name="beatle" /> Ringo</label></li>
+</ul>
+
 # CheckboxSelectMultiple Widget ###############################################
 
 >>> w = CheckboxSelectMultiple()
@@ -783,6 +804,11 @@ u'<ul>\n<li><label><input type="checkbox" name="nums" value="1" /> 1</label></li
 u'<input type="text" class="big" value="john" name="name_0" /><br /><input type="text" class="small" value="lennon" name="name_1" />'
 >>> w.render('name', 'john__lennon')
 u'<input type="text" class="big" value="john" name="name_0" /><br /><input type="text" class="small" value="lennon" name="name_1" />'
+>>> w.render('name', 'john__lennon', attrs={'id':'foo'})
+u'<input id="foo_0" type="text" class="big" value="john" name="name_0" /><br /><input id="foo_1" type="text" class="small" value="lennon" name="name_1" />'
+>>> w = MyMultiWidget(widgets=(TextInput(attrs={'class': 'big'}), TextInput(attrs={'class': 'small'})), attrs={'id': 'bar'})
+>>> w.render('name', ['john', 'lennon'])
+u'<input id="bar_0" type="text" class="big" value="john" name="name_0" /><br /><input id="bar_1" type="text" class="small" value="lennon" name="name_1" />'
 
 # SplitDateTimeWidget #########################################################