windows cell card internet to macbook via ethernet

OK so im going to florida and my dads pc has a sprint pcmia cellular card. i want to connect my new macbook to it via ethernet so i can use internet. if i connect it now in my macs network settings all it says is ethernet
self assigned ip address
if i click on it it says connected has self assined ip address may not be able to connect to the internet

Yes, because you need to enable Internet Connection Sharing in your Dad's computer. You might wanna check out some windows forum to figure out how to do that.