Strange 802.11 traffic

Hey guys!

I'm no expert in Wireshark or 802.11. But we have here a situation. Our Core (Catalyst 4507) is having high cpu all day. Cisco TAC says that some traffic with mac address 00:00:00:00:00:00 is hitting it's CPU pretty hard (80-95%) and that traffic is coming from the port where the wireless controller (Cisco WLC 5508) is connected.

I sniffed the core interface where this WLC is connected during 10 minutes. I got 321213 packets and 53% of those packets are those with mac-address 00:00:00:00:00:00. Digged a little deep and found that they were something called Probe Request.

I uploaded a sample capture of those probe requests do CloudShark

My questions are: 1- Is this probe request normal? 2- Is this supposed to make the CPU go that high?

Thanks!