array_key_exists ERROR updating to GS 3.2.1

[D.O.]

Ah no sorry, that is one of my last try....
The real lines are these...

PHP Code:

<?php getPageField('centerfold','pubDate'); ?>
<?php getPageField('centerfold','title'); ?>
<?php getPageField('centerfold','metad'); ?>

I am very desperate because everything was okay with version 3.2.0 and now it's gonna be a puzzle..
Of course "centerfold" is an existing page and it is not a private one.