[manasecret]

Ummm... don't know much about your particular situation. Let's start with this:

What connection does your blackberry use to share the internet? A USB cord, a network cable, .... ?

On another note, I know Sprint now offers a 4G wireless router that does exactly what you want out of the box. Of course, the 4G service would be through them, which may not reach your rural area yet.