Dell Axim X3 Auto Connect

I have several axium x3 working in vehicles, plus a linkys wireless router, what i need the PDA's to do is detected a my local network via wireless, automaticly (even though it may go out of range of the network and then come back into the network), and sync any application on it, such as databases automaticly at a defined time, or when it gets within range those will be definable chocies on the application that will be created. I need this created within 7 Days after award. Now do not post generic stuff i want to see that you read the detail.