don't fatal if we don't know how to handle a program: drop the packet on the floor instead
don't fatal if we don't know how to handle a program: drop the packet
on the floor instead

sit/dht,weidezhang/dht,sit/dht,sit/dht,weidezhang/dht,weidezhang/dht,sit/dht,sit/dht,weidezhang/dht,weidezhang/dht