SNMP request returns a wrong string with the mib browser

Hi,

I have a problem with a mib. The mib is IDIRECT_REMOTE_MIB. These are examples:

1 /
# snmpwalk -v2c -c public 172.16.6.100 .1.3.6.1.4.1.13732.1.4.5.1.5
IDIRECT-REMOTE-MIB::latencyvalue.5026313 = STRING: 587.60
IDIRECT-REMOTE-MIB::latencyvalue.5038053 = STRING: 534.02
IDIRECT-REMOTE-MIB::latencyvalue.5038276 = STRING: 525.75
...

With OpManager Mib Browser (or a custom monitor) I have:
latencyvalue.5026313:553.40��0|��{��|��|��|��|��|��|�?�l��{� �{� �{�䁄y�l�� |��o�p�� ....
��5��P�
latencyvalue.5038053:530.82��0|��{��|��|��|��|��|��|�?�l��{� �{� �{�䁄y�l�� |��o� �|��}��؆�D��)��$��callback: 1 on fd
.....

2 /
# snmpget -v2c -c public 172.16.6.100 .1.3.6.1.4.1.13732.1.4.5.1.5.5026313
IDIRECT-REMOTE-MIB::latencyvalue.5026313 = STRING: 565.73

With Opmanager:
latencyvalue.5026313:564.20��0|��{��|��|��|��|��|��|�?�l��{� �{� �{�䁄y�l��
....
��5��
latencyvalue.5026313:553.40

I would like to know why i have a such result. Is there a way to get back only the last line?

Thank you