Sprint is CDMA technology, which doesn't use SIM chips. .
Have you contacted Sprint about service plan and provision this on their network? I would also verify the location you plan to use this has EVDO RevA coverage from Sprint. You don't want 1xRTT it's too slow! Sprint needs the ESN (Electronic Serial Number) to active it. I would verify you have the right model for Sprint (HWIC-3G-CDMA-S) versus Verizon.