Timeout Session

Hi,
First of all thanks for the plugins which work great.
We just have a little problem with the diskused option.
We are monitoring about 70 volumes on a fas8020 CDOT.
Sometimes, all volumes are turning red with an out of bound return code. Those false positive are resorbed with a recheck.
I tried to change the SNMP timeout session as ebardellidoxee says :

1) Manage SNMP timeout.
my ($sess, $err) = Net::SNMP->session( -hostname => $server, -version => $version, -community => $comm, -timeout=> 60);
If you don’t specify any value, the default is 5 secs and in a busy environment it misses lots of packets. You might add a flag that populate the –timeout parameter of the Net::SNMP->session

But when I change it I got a general error of this plugin.
It seems that the timeout parameter for snmp session is not good.

Did someone encounter the same problem and how to solve it ?
Thanks,
regards