Field (not instance) settings not saving on field configuration form

The field configuration form (admin/build/node-type/NODETYPE/fields/FIELDNAME) includes the instance settings at the top and some field (non-instance) settings (cardinality and whatever the field type defines as a field setting as opposed to a widget setting) at the bottom. Changes to field settings aren't saving. This makes it impossible to set cardinality to anything other than 1. We need to either update cck_field_edit_form_submit() to save the cardinality and other field settings, or move the cardinality and other field settings exclusively to the admin/build/node-type/NODETYPE/fields/FIELDNAME/field-settings form.