Please try:
arp -v -i eth1 -s <ipaddr> <hw_addr> temp
Does it work? OK.
It is my fault, I beg pardon. Try also:
arp -v -i eth1 -s <ipaddr> <hw_addr> com
(I am not sure, that you arp utility has "com" option)
I'd not like to fix it in the kernel.
I hope, the next net-tools release will make it correctly.
Alexey Kuznetsov.