Change journal is supported only on NTFS volumes; you need to have change journal enabled on the drive. Also you need to have a saveset at top level of the drive, not a subfolder.
Windows 2008 is VSS only right? see below which is copied from the article.
Microsoft Windows Change Journal is a Windows Server 2003, Windows XP Professional, and Windows 2000 file system feature that logs a record of each change as it occurs to the files and directories on a local NTFS 5.0 volume.
The Change Journal enables NetWorker software to detect more types of changes and save more changed files than is possible when not using the Change Journal. Additionally, the Change Journal improves NetWorker performance.
The Change Journal can be enabled or disabled independently for each NTFS 5.0 volume. When enabled, the Change Journal stores records of the volume's file and directory changes in System Volume Information\tracking.log.
Note: When VSS is used, the Microsoft Change Journal is not used. Microsoft Windows Vista and Windows Server 2008 are VSS only, so Windows Vista and Windows Server 2008 do not use the Windows Change Journal.