error_reporting() will always return 0 when in the context of code prefixed by "@"

" It is important to remember that the standard PHP error handler is completely bypassed. error_reporting() settings will have no effect and your error handler will be called regardless - however you are still able to read the current value of error_reporting and act appropriately. Of particular note is that this value will be 0 if the statement that caused the error was prepended by the @ error-control operator."

See: http://us2.php.net/manual/en/function.set-error-handler.php

See previous comment.