[bdurst08]

Yeah What he said ^
Dude that sucks! let me guess he is no longer with sprint?
just adding my 2 cents. But to answer your question, from what remember from my days w/ sprint. That no you will not be able to do that. There is another # that linked to the phone and ur buddy's account called the ESN. Thats what preventing you from activating it on ur account. I have haven't heard of anyone being able to get them to do that, but it might be able to be done. Maybe someone will be able to give you more info than I can.
Hope I was able to help even a little bit. Good Luck, tell your buddy to pay his damn phone bill!! HAHA