Ok. I’ve found out what’s causing my initial error.
PHP Fatal error: Call to undefined function utf8_decode() in /var/www/blaat.info/manager/processors/save_content.processor.php on line 564, referer: http://www.blaat.info/manager/index.php?a=27&id=1
My databaseformat is UTF8_unicode, Modx default character encoding is Unicode(UTF-8) - utf8. Changing this to Unicode-unicode or Western European (ISO) iso-8859-1 fixes my problem.
