Can't switch between XT9 and ABC

[sl8763]

I'm sure this is a stupid question...but how do I switch between XT9 and ABC input? Everything that I can find says I just need to tap the XT9/ABC toggle button when the on-screen keyboard is up - but that button is never green, it is always grayed out. Right now I'm stuck in ABC mode and I'd like to try XT9. I am running the stock Sprint 6.5 ROM.

I've tried doing it in a bunch of different screens and fields, thinking that I could only do it in certain areas, but I can't locate a field that will let me change it. Done plenty of soft resets. Anyone know what to do? Thanks!