I don't understand why you say Android is not Linux. Android is a very lightly forked Linux kernel and the kernel/userspace API is almost fully compatible with GNU/Linux. In any case I used eglibc. It even works fine for system scripts that use /system/bin/sh.
I would love to make mksh work. Where do I put the .mkshrc file on my Android phone in order to make it load whenever I start the shell?