DP 6.1 Domino Integration

I've the following issue with Domino integration.
When doing an incremental backup of the notes server several of the following messages are logged .

[Minor] From: OB2BAR_LDBAR@srv-notes.xxx.xxx "PCOTTO-NOTES" Time: 7/23/2009 12:46:59 PM
Lotus Notes C API 'NSFIsNewBackupNeeded' returned error 5063: Function not supported for pre-R5 format databases.


The problem is that the domino server version is 7.0.4
The domino server is part of domino domain with other servers , 7.03, and the domino administrator told us that the files format are not below 5

thanks