Module causes errors itself

The module makes a multidimensional array out of the $edit variable (by adding the user roles capable of using the form), and then when a new field is requested to be added, tries to store the array elements in hidden form fields to preserve their values. Multidimensional arrays are not to be htmlspecialchars()-ed (neither passed on as usual strings anyway), so the new field addition loses the role information. I don't have a good idea how to solve the problem, but it is quite nasty...