Is there a way to modify this plugin or if there is a setting I have missed to get special characters working?

I've tried to use mxFormBuilder with a page made in german, but all special characters are changed to html encoded characters. So characters like åäö are converted to öäåö.
Any suggestions on how I can fix this?

This is a great plugin by the way! Good work!

45    $this->properties[$this->modx->sanitizeString($p)] = !is_array($v) ? htmlentities($v) : $this->modx->sanitize($v);

45   $this->properties[$this->modx->sanitizeString($p)] = !is_array($v) ? htmlentities($v,ENT_QUOTES,'UTF-8') : $this->modx->sanitize($v);