The Notes 8 and 8.5 ODS (object data store...aka, NSF file) do not use the latest version by default. The 8.x version lets you compress design elements and data to save disk space and also use DAOS (8.5) to save space for attachments. Lotus does not enable the new ODS when you install the server because some backup and antivirus programs don't know what to do with the new format.
If you want the 8.5 ODS, add "Create_R85_Databases=1" to your notes.ini file for the server.
If you want the 8.0 ODS, add "Create_R8_Databases=1" to your notes.ini file for the server.
These switches will let Domino create databases in the new format for new databases.
To convert existing databases to the new format, you have to run the compact command using these parameters:
-c (copy style compact)
-n (design compression)
-v (data compression)
-daos on (to pull attachments out of the NSF and into DAOS -- assuming DAOS has been configured on the server document).
The command line would be (run it from the command line to convert names.nsf and log.nsf and other databases the server might be using at the time:
[n]compact -c -n -v -daos on