diff --git a/Source/NSUserDefaults.m b/Source/NSUserDefaults.m
index b8c8aa8c9..cac2b8a3b 100644
--- a/Source/NSUserDefaults.m
+++ b/Source/NSUserDefaults.m
@@ -696,13 +696,13 @@ static NSMutableString   *processName = nil;
 	val = [enumerator nextObject];
 	if (!val)
 	  {            // No more args
-	    [argDict setObject:nil forKey:key];
+	    [argDict setObject:@"" forKey:key];		// arg is empty.
 	    done = YES;
 	    continue;
 	  }
 	else if ([val hasPrefix:@"-"])
 	  {  // Yet another argument
-	    [argDict setObject:nil forKey:key];
+	    [argDict setObject:@"" forKey:key];		// arg is empty.
 	    key = val;
 	    continue;
 	  }