Question : Unknown client DHCP Broadcasts SCOPE FULL

We use W2003 standard with a DHCP scope. Within 30 minutes the DHCP leases are all occupied with clients who are unknown to us. The clientname looks like an MAC adress, the vendor id is IBM (We use IBM, so thats no surprise). I investigated the MAC addresses but they are nowhere to be found. Our network operator has followed the DHCP broadcast and it looks like its comming from all kind of machines, but they all have DHCP disabled. Can anybody give me a clue where to look any further?

Answer : Unknown client DHCP Broadcasts SCOPE FULL

We've found the problem. The Baseboard Management Controller in specific types of the IBM x-series have DHCP enabled.... ! Thank you very much for you support.