The curation task 'requiredmetadata' reports items even though the metadata that is required for their type is present. I seems that the curation task does not consider the type-bind parameter in input-forms. Fields which are required for some types only (see example below) seem to be considered by the curation task to be required for all types.
<required>This field is required.</required>
<type-bind>book, conference proceedings</type-bind>
To recreate the problem run the curation task on an item that is neither "book" nor "conference proceedings" (dc.type).