Forums / Cotonti / General / Page Avatar fail

I have another trouble:

Image is not uploaded correctly and thumb is not created at all

in apache2 error logs I see

PHP Strict standards:  Only variables should be passed by reference in /HIDDENPATH/plugins/pageavatar/pageavatar.page.add.first.php on line 32, referer: http://HIDDENDOMEN/offer?m=edit&id=6

so, it is about this line:

$file_ext = mb_strtolower(end(explode(".", $pageavatar["name"])));

What would be your guess? I understand, author recommends to use pageMavatar instead, or I'm wrong?