trapsess instead of trap2sink

Hi,
 
I'm using send_v2trap in my snmpd and snmptrapd receives the traps with
the following snmpd.conf:
 
rwcommunity  my_rwc
trap2sink  localhost
 
If I'm trying to use trapsess instead as follows
trapsess -v 2c -c my_rwc localhost
 
the traps are not sent any more. I've started the trap receiver like
this:
snmptrapd -On -f -Le -d
 
and nothing comes out,
 
Is something more I have to add to trapsess parameters?
 
Thanks,
Eugen