arp -a takes 40 secs to display cached MAC addresses. Is this normal?

[boink]

Dear FreeBSD,

# uname -a
FreeBSD MyFBSD.int.vir 6.0-RELEASE FreeBSD 6.0-RELEASE #0: Thu Nov  3
09:36:13 UTC 2005    
root at x64.samsco.home:/usr/obj/usr/src/sys/GENERIC  i386

# /usr/bin/time -h arp -a
MyFBSD (10.1.2.1) at 00:00:f8:10:6c:8a on dc0 permanent [ethernet]
MyFirewall (10.1.2.254) at 00:0d:b9:11:a5:b9 on dc0 [ethernet]
? (10.1.2.255) at ff:ff:ff:ff:ff:ff on dc0 permanent [ethernet]
        40.22s real             0.00s user              0.00s sys
           ^
...where:

# ifconfig
dc0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
        options=8<VLAN_MTU>
        inet6 fe80::200:ff8f:fe01:6a3a%dc0 prefixlen 64 scopeid 0x1
        inet 10.1.2.1 netmask 0xffffff00 broadcast 10.1.2.255
        ether 00:00:f8:10:6c:8a
        media: Ethernet autoselect (100baseTX <full-duplex>)
        status: active
rl0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
        options=8<VLAN_MTU>
        inet6 fe80::240:f4ff:fec3:54f5%rl0 prefixlen 64 scopeid 0x2
        inet 10.1.1.98 netmask 0xffffff00 broadcast 10.1.1.255
        ether 00:40:f4:c4:a4:6e
        media: Ethernet autoselect (100baseTX <full-duplex>)
        status: active
ed0: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1500
        inet6 fe80::2e0:7dff:fe43:e259%ed0 prefixlen 64 scopeid 0x3
        ether 00:e0:7d:67:5e:a8
        media: Ethernet autoselect (10baseT/UTP)
plip0: flags=108810<POINTOPOINT,SIMPLEX,MULTICAST,NEEDSGIANT> mtu 1500
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384
        inet6 ::1 prefixlen 128
        inet6 fe80::1%lo0 prefixlen 64 scopeid 0x5
        inet 127.0.0.1 netmask 0xff000000

Notes:
- everything else on 10.1.[1,2].0/24 is switched off currently - the
arp list is in fact complete
- ed0 has no IP address (outside the firewall, for sniffing purposes)
- I'm not experiencing any networking issues
- IIRC this happened on Free BSD5.3, too

Is this expected behaviour?  Just curious.

Best wishes,
boink

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