Right soft key locked to "t-zones", how do I change this?

Sorry if this is a repost, I did a search first but found nothing.

I just bought a new Nokia 6301 from T-mobile and my right soft key can't be changed from anything but the useless "t-zones" function.

In the setup menu ("My Shortcuts") there are customization options for the left soft key, and the four nav keys in the middle, but the right soft key settings are notably absent.

Is there an easy way to customize this key's function?

I know there is no way of changing it on mine, I have the 5310 XpressMusic but I'm not sure as to others.