diff -r 95d1adf144ee Lib/argparse.py
--- a/Lib/argparse.py	Sat Nov 03 14:37:37 2012 +0200
+++ b/Lib/argparse.py	Sat Nov 03 16:57:54 2012 +0100
@@ -2229,7 +2229,11 @@
                 value = action.default
             else:
                 value = arg_strings
-            self._check_value(action, value)
+            if not isinstance(value, list):
+                self._check_value(action, value)
+            else:
+                for v in value:
+                    self._check_value(action, v)
 
         # single argument or optional argument produces a single value
         elif len(arg_strings) == 1 and action.nargs in [None, OPTIONAL]:
diff -r 95d1adf144ee Lib/test/test_argparse.py
--- a/Lib/test/test_argparse.py	Sat Nov 03 14:37:37 2012 +0200
+++ b/Lib/test/test_argparse.py	Sat Nov 03 16:57:54 2012 +0100
@@ -819,6 +819,18 @@
     ]
 
 
+class TestPositionalsNargsZeroOrMoreChoices(ParserTestCase):
+    """Test a Positional that specifies unlimited nargs with choices"""
+
+    argument_signatures = [Sig('foo', nargs='*', choices='abc')]
+    failures = ['-x', 'spam']
+    successes = [
+        ('', NS(foo=[])),
+        ('a', NS(foo=['a'])),
+        ('a b', NS(foo=['a', 'b'])),
+    ]
+
+
 class TestPositionalsNargsOneOrMore(ParserTestCase):
     """Test a Positional that specifies one or more nargs"""
 
@@ -830,6 +842,17 @@
     ]
 
 
+class TestPositionalsNargsOneOrMoreChoices(ParserTestCase):
+    """Test a Positional that specifies one or more nargs with choices"""
+
+    argument_signatures = [Sig('foo', nargs='+', choices='abc')]
+    failures = ['', '-x', 'spam']
+    successes = [
+        ('a', NS(foo=['a'])),
+        ('a b', NS(foo=['a', 'b'])),
+    ]
+
+
 class TestPositionalsNargsOptional(ParserTestCase):
     """Tests an Optional Positional"""