This is not just a problem with new PCs -- our older Xerox Phaser 860DX and WorkCentre C2424 printers have mfr's preambles of "08:00:11", and an old Amiga 2000 NIC has a preamble of "ae:00:00" (Ariadne, I think). We're talking as far back as early-early nineties here people, 10BASE2 was king and some 10BASE5 was still out there.
It's really surprising that D-Link designers didn't take this into account. Evidently they didn't read the RFCs very well -- IEEE 802.x addresses beginning with octets other than "00" have been around for a long time. (The first mention of "ETHERNET NUMBERS OF INTEREST" is found in RFC 820, January 1983, and lists initial octets 02, 06, and 08).
Also, the DIR-825 is not the only D-Link product to have this issue -- the new DIR-330 VPN router we just purchased is buggy as well in the DHCP server, and no new firmware yet (IIRC, our older DI-514, DI-524, and DI-628 didn't have the issue).
I'm really aggravated that I can't deploy the hardware until this is fixed; and since it's a such silly goof, I certainly expect the dev's to have this on the top of their list. It should be a real simple fix -- just don't look at the initial octect at all. If somebody typed it wrong, it can be fixed easily enough -- I don't know why they bothered with the extra code to check it in the first place.