why phone send gateway ip detect packet

[pig_tails]

i use t31p ip phone,the phone send arp packet like below in every 12 hours or when it start:
sender mac:the phone mac
sender ip:0.0.0.0
target mac:0000-0000-0000
target ip:the gateway ip
because these arp packets are used for ip conflict detecting,when the gateway device receive these arp packets,it thinks there having a device which want to use a ip address it had already used,so the gateway device generate a ip conflict messages.
because the gateway are defined on my switch,so my switch is continuous generate these ip conflict messages，how can i sovled this problem，any suggestion is appreciate.