Securing dbasis with the standard, Syntax session-based authentication turns out to be relatively simple. The version of dbasis in cvs now has this for all future sites going forward. To secure exisiting instances drop in the following code after line 115. This requires a login from a user in the admin group.
line 115: $session->initialize();
# Authentication
# --------------
require_once($PXDB_PATH . '/classes/auth/pxdb_auth.class.php');
$auth = &new pxdb_auth('dbasis');
$auth->set_username_field('idnum');
//$auth->debug = true;
// restrict to admin group
if($_GET['logout']) { $auth->logout(); }
$auth->restrict( 'admin' );
if(!($user = &$auth->authenticate())) {
//include(SITE_ROOT . '/display/header.disp.php');
$auth->showlogin();
//include(SITE_ROOT . '/display/footer.disp.php');
exit;
}