arp proxy question

[Wojciech Puchar]

i added pub entry in ARP table

? (XX.YY.ZZ.92) at d4:ae:52:bb:82:4f on bge0 permanent published [ethernet]

(normal server addresses are .90 and .91)

and run vtun tunnel to other computer from this server tunneling this .92 
address there.

tunnel works fine

tun2: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> metric 0 mtu 1500
         options=80000<LINKSTATE>
         inet XX.YY.ZZ.90 --> XX.YY.ZZ.92 netmask 0xffffffff
         Opened by PID 81626


the result is as below:

# ping XX.YY.ZZ.92
PING XX.YY.ZZ.92 (XX.YY.ZZ.92): 56 data bytes
36 bytes from XX.YY.ZZ.92: Destination Host Unreachable
Vr HL TOS  Len   ID Flg  off TTL Pro  cks      Src      Dst
  4  5  00 0054 ee9c   0 0000  40  01 e752 XX.YY.ZZ.90  XX.YY.ZZ.92

64 bytes from XX.YY.ZZ.92: icmp_seq=1 ttl=64 time=10.788 ms
64 bytes from XX.YY.ZZ.92: icmp_seq=2 ttl=64 time=12.254 ms

except this above everything is OK.

what i do wrong?