Android - Is it possible to set device's Latitude and Longitude using ADB SHELL?

this is possible using ADB shell:

$ telnet localhost 5554
Android Console: type 'help' for a list of commands
geo fix -82.411629 28.054553

Please read:

To add to Jared's answer (can't comment - not enough reputation yet :/). This works with the emulator only so I wrote an app you can run on a real device and it provides exactly the same interface (telnet to :5554 and run "geo fix ..." or "geo nmea"): MockGeoFix