Which message forms are migrated per the default settings with Migrator for Notes to Exchange (MNE)? (4347995)

Some message forms might not migrate with Notes Migrator for Exchange and the following warning might be displayed in the migration logfile:

1595414: 18:15:08 WARNING: [7342-4-7-00000000] Message was filtered or skipped because: Not migrating unknown message form: REPLY1
1595415: 18:15:08 ID for filtered message:
1595416: 18:15:08 Msg: (OF5AB3F55F:C03CDA60-ONC12577D0:004950AF)
1595417: 18:15:08 Folder: (~INBOX)
1595418: 18:15:08 Subject: (Message subject)
1595419: 18:15:08 Sender: ("User A" <usera@domain.com>)
1595420: 18:15:08 Date: (Wed Nov 03 14:24:32 2010)
1595421: 18:15:08 Original message: notes:///C12568480054D5E5//5AB3F55FC03CDA60C12577D0004950AF

Which message forms are migrated per the default settings with Migrator for Notes to Exchange?