Hi,
If you are talking about routers then yes there is a way, but on PIX firewall I dont think so.
Here is a sample, you can get the relevant inforamtion from http://www.cisco.com/warp/public/707/cisco-sn-20030820-nachi.shtml
Some thing like this
access-list 199 permit udp any any
route-map blockudp35 permit 10
match ip address 199
match length 32 32
set interface Null0
interface
ip policy route-map blockudp35
Thanks
Nadeem