SharePoint 2010 plugin: getListItems does not get all discussion board items

Only one row is being returned from our MCPermissions plugin when trying to enumerate a Discussion Board list. This link describes the problem:

http://social.msdn.microsoft.com/Forums/sharepoint/en-US/afe07483-6aec-424a-9434-c8e8b963e55c/how-to-get-all-the-items-from-a-discussion-board?forum=sharepointdevelopmentlegacy

The solution (using the Items member) is not viable in our case because it does not page the results. And yet there is no CAML example that would show how to get the missing rows.