Scaffolding and .htaccess

[eluser]chinathong[/eluser]
hi. I have configured my app with an .htaccess file so to remove the index.php from the urls, I also configured my config.php file with $config['base_url'] = "http://localhost/~username/appname" ... it's working just fine, but I noticed that when using the scaffolding helper I have to explicitly use "index.php" in the url ... that's fine for me, but I'd like to know if there is an extra configuration that I'm missing here. Thanks in advance :-)