Hoster blocking php config changes?

my client gave me access to the shared hosting (that he chose and paid) for a website I'm doing. PHP is running as CGI. I can't change PHP settings through ini_set at all! Is this possible? Is this a standard practice of shared hosting? What I basically need to do is to JUST activa开发者_开发百科te errors! How can they expect someone to work with blank pages as "errors"!

Unless they've seriously locked down settings:

ini_set('display_errors', 1);
error_reporting(E_ALL);

should be all you need.