The Heirloom Bourne Shell project is used in Fedora, so that's how it came up. I don't know if it's used elsewhere or if this variant of the license, but any info on that would be helpful!

I wonder why they are using the Caldera license?

Did they harvest these files from the 7th Edition of Unix, or did Sun license these and Caldera made them put this license on things? The version 7 /bin/sh was included in the grant of the original license, and the System V version was excluded which is what the OpenSolaris one is based on if it came from Sun's repo... But I've not done the software archaeology to know from whence this project started their sources...