I have 2 Panasonic Cordless phones, one a 2.4 GHZ & one is a 5.8 GHZ being used into a Magic Jack DSL Connection. Can the 2.4 Ghz phone be changed to 5.8 GHZ to use as an extra Satellite phone?

How many ports does your magicjack has? Mine is only 1 and I'm using 2.4 GE ghz and it works fine. If it loses charge, I just switch phone with the regular analog one.

You can use both, the 2.4 and 5.8 Ghz on the same line. You will need a 5.8 gig phone to match existing to use as an extra phone on 5.8.
May have to enroll, register, learn, or whatever the manufacturer calls it.

how many ports does your magicjack has? Mine is only 1 and im using 2.4 GE ghz and it works fine. If it loses charge, i just switch phone with the regular analog one.

I guess I didn't explain properly. What I want is an extra HANDSET for the 5.8 ghz plugged into the Magic Jack. I have a 2.4 ghz on a spare phone. What I wanted to know is,
There any way by changing the freq of the spare to 5.8 ghz so it can be used as a spare handset? If so, how to do it?

It may be possible, but not economically fesiable.