Can a jailbroken iphone 4 be used as a tracfone/prepaid phone?

I have an iPhone 4 on verizon and am going to be upgrading soon. My boyfriend, whos not exactly into the whole hype of having a phone, but he knows he needs one, wants to get a tracfone or something prepaid.
If I jailbrake my iphone (its way past its warrenty anyways) would he be able to use it for tracfone or prepaid service?
Also is there any other fees and such if he were to do this?

Thanks for any information! :)

No, you would need a att iphone(gsm) to use as prepaid on those networks