how can i receive calls/texts from old phone on new phone?

ok…so heres the deal…i have an old samsung cell phone with t-mobile that i’ve had for about 4 years. So i upgraded to a HTC TouchPro2 with Sprint. But I can’t transfer my old number over until after June 14.

So what i want to know is this:
Is there a way for me receive incoming calls/texts from the old phone onto the new phone…is there a call/text forwarding feature like there used to be on landlines? or could i do it through a bluetooth connection or a wi-fi connection between both phones?

Its just for about 10-days and i don’t get enough phone calls or texts to warrant carrying around two cell phones.

any thoughts/suggestions would be greatly appreciated! thanks!