Normally you cannot, due to incompatabilities because of CPU voltage and, and the fact that the BX chipset is for SLot 1 Processors. But there IS HOPE (depending on what Motherboard your friend has) Its the ::

owerLeap PL-iP3/T Rev 2.0::: You can pop in a 1.4GHZ P3 512K 133FSB on a BX board OOHH YEAH!!!! I have a Celeron 1.3 256K on a Asus P3CL (i820) It works fine and CPU ID see's it as a 1.3 GHZ Celeron. I'd highly recommend it get it at
PowerLeap or look around google and find a reatiler selling it for 50 bucks (NO cpu) get a CPU at newegg and let it fly. Good Luck.