diff -r 54fb77e0762c -r 741438d60249 Lib/argparse.py
--- a/Lib/argparse.py	Thu Jun 23 14:22:59 2011 +0200
+++ b/Lib/argparse.py	Fri Jun 24 00:23:46 2011 +0200
@@ -2000,7 +2000,7 @@
         for arg_string in arg_strings:
 
             # for regular arguments, just add them back into the list
-            if arg_string[0] not in self.fromfile_prefix_chars:
+            if not arg_string or arg_string[0] not in self.fromfile_prefix_chars:
                 new_arg_strings.append(arg_string)
 
             # replace arguments referencing files with the file content
diff -r 54fb77e0762c -r 741438d60249 Lib/test/test_argparse.py
--- a/Lib/test/test_argparse.py	Thu Jun 23 14:22:59 2011 +0200
+++ b/Lib/test/test_argparse.py	Fri Jun 24 00:23:46 2011 +0200
@@ -1371,6 +1371,7 @@
         ('X @hello', NS(a=None, x='X', y=['hello world!'])),
         ('-a B @recursive Y Z', NS(a='A', x='hello world!', y=['Y', 'Z'])),
         ('X @recursive Z -a B', NS(a='B', x='X', y=['hello world!', 'Z'])),
+        (["-a", "", "X", "Y"], NS(a='', x='X', y=['Y'])),
     ]