Pretty much every where besides the US (and japan, and a few other places) use the GSM standard, so that phones are interchangable between all the providers. Thus, no one worries about phones being compatible with providers except here in the US. We've got at least four different competeing standards, with GSM, CDMA, TDMA and whatever Nextel uses(iDen?). In short, sprint phones are sprint phones and you have to use ones the provided. If you want to use a P800, you'll have to switch to Cingular, T-Mobile or AT&T's new GSM network. (at least in california)

Matthew