Problem with removing mac address from arptable on 10-stable

[Marcelo Gondim]

Hi all,

I'm having this problemon my FreeBSD 10-STABLE:

(root at rt01)[~]# arp -an|grep 187.xxx.216.252
? (187.xxx.216.252) at 5c:e0:f6:00:11:29 on vlan4 permanent [vlan]

(root at rt01)[~]# arp -d 187.xxx.216.252
delete: cannot locate 187.xxx.216.252

FreeBSD rt01.xxxxxx.com.br 10.0-STABLE FreeBSD 10.0-STABLE #8 r265409: 
Tue May  6 01:14:05 BRT 2014 
root at rt01.xxxxxx.com.br:/usr/obj/usr/src/sys/GONDIM  amd64

This is a real problem or am I missing something?

Thanks and best regards,
Gondim