looks like magic jack is a voiceoverIP adapter... officiall drivers only exist for windows and mac, so i dont think it will be easy to let this run via pogoplug... maybe you can get an old pc from anywhere (second hand ect.) for 30 bucks or less and set this up as "phoneserver"... would be my idea :D

Greets!

Your best bet would be to buy an ATA (analog telephone adapter) and set it up for use with magic jack service instead of the magic jack device. I have a linksys pap2t-na http://en.wikipedia.org/wiki/Linksys_PAP2 and it works very well with call-centric service. I have not tried it with magic jack, although I have heard that it works.