piranha udp problem

["tao cui" <taocui@xxxxxxx>]

hi all:
    i am using the piranha-0.7.0-3 to config the lvs, the tcp request works 
well,but the udp can't work,if i use ipvsadm, it shows:
    Prot LocalAddress:Port Scheduler Flags
     -> RemoteAddress:Port          Forward Weight ActiveConn InActConn
   TCP  10.151.11.244:domain rr
      -> 10.151.11.243:domain         Route   1      0          0         
   UDP  10.151.11.244:domain rr
the UDP redirection does work if I try:
    ipvsadm -a -u 10.151.11.244:53 -r 10.151.11.243 -g -w 1
ipvsadm returns:
    Prot LocalAddress:Port Scheduler Flags
     -> RemoteAddress:Port          Forward Weight ActiveConn InActConn
   TCP  10.151.11.244:domain rr
      -> 10.151.11.243:domain         Route   1      0          0         
   UDP  10.151.11.244:domain rr
      -> 10.151.11.243:domain         Route   1      0          0         

why can't i config the udp through the piranha?

thanks