Add missing button images
Remove workaround for PHP bug #49692

PHP bug #49692 [1] affects only PHP 5.3.0 and was fixed in PHP 5.3.1.
I think it is time to remove the workaround as PHP version 5.3.0 is
end-of-life for a long time now and even Debian old-stable comes with
PHP 5.3.3.

[1] <http://bugs.php.net/bug.php?id=49692>