Problem with snmp (NV+ 4.1.13)

[bibi21000]

I've activated the snmp agent and retrieve this data using munin.
After 5 days, the readynas-agent use a huge of memory :

 
...
924 root      15   0  8080   3424   2160 S  0.0   1.5    109:36.45  snmpd
930 root      15   0  7648   1696   1280 S  0.0   0.7       0:00.16  snmptrapd
934 root      15   0  346m  157m  1472 S  0.0   71.4    22:05.02  readynas-agent
...

Any idea ?
TIA