Data not available. BRIDGE-MIB might not be implemented in t

Hi,
i have install new cisco2960TT now i want to do switchport mapping using tool which comes with opmanager 6 but it isn�t working giving me error sayign

�Data not available. BRIDGE-MIB might not be implemented in this device �

i have seen that this mib is install in the server...also in the switch.
rest of the switches in the network in able to do switchport mapping. with the tool opmanager ..only the new switches i m not able to i dont knwo the reson why.

But when i try switchport mapping with �OPUTIL� with the same cisco2960TT IT WORKS�S
WHAT CAN BE THE SOLUTION,

BEST REGARDS & THANKS IN ADV.