How to connect to a bluetooth internet connection?

I have an iPhone 3GS and a Samsung Galaxy Ace GT-S5830. I have bluetooth tether on in my iPhone and I would like to connect my Galaxy Ace to it. When I tried connecting the Ace in the settings, ont he iPhone it said that the device was unsupported.So, what are my options? I can't use 3G on the Ace because it's FAR too costly.

So use an iPhone app that creates a Wi-Fi hotspot and use the iPhone's internet via Wi-Fi.