Broken back-end

Using custom contacts form, I have ever since upgrading to version 4.5.3 been seeing this error message on the backend dashboard:

Warning: array_shift() [function.array-shift]: The argument should be an array in /home/apadmin/public_html/wp-content/plugins/custom-contact-forms/modules/widget/custom-contact-forms-dashboard.php on line 22

As such the plugin continues to work. But doesn’t look nice.