Since the thread opener never gave the bpmount or bpbkar entries this is just a very good guess. Some Unix filesystems, like LOFS in Solaris 10 zones, are treated like NFS shares. In normal backups you can check the "follow NFS"-option in the policy settings. I once had a long conversation with the support, and it's not possible to make the SAP-Agent backup NFS shares, or what NetBackup thinks is NFS.
We're using the Oracle agent now - it doesn't have this "feature" and is much cheaper. The only trouble is, that the SAP Logfiles (sapbackup, saparch) will not be automatically backed up by the brtools. This would require the SAP-Agent additionally. I solved this by adding a bpbackup-call at the end of the backup script...