I think you need the latest BIOS flash to run the newer P3 CU Mines, but hardware wise, it should be able to run the CPU.
The only thing to remember is the BE6-2 has no 1/2 AGP divider, so your AGP port will be running out of its 66Mhz normal spec.
Chances are your AGP will be ok, but there a few AGP graphics cards out there which dont like running even 1 or 2 Mhz out of spec.