Find the new NBU_DLO_61_6_M maintenance packs for x86 and x64 here:

DLO 6.1MP6 Release Information
 http://symantec.com/docs/TECH154499

The Compatibility Matrix has been updated as well:

NetBackup (tm) Desktop Laptop Option (DLO) 6.x Compatibility Matrix
 http://symantec.com/docs/TECH50108