This patch add following features to ipfw:

# ipfw set N {show | list} [N | N-M]
List rules from specified set.

# ipfw set N delete M 
Delete rule M from set N.

# ipfw set N {resetlog | zero} M
Reset counters of rule M from  set N.

# ipfw set N flush
This command is similar to `ipfw delete set N`

(c) Andrey V. Elsukov <bu7cher [at] yandex.ru>