Balsa compile/install fails: 'Unable to write cache file'

[Lennon Cook <maguswizardo gmail com>]

I am compiling Balsa-2.3.5 on a Linux From Scratch system. The 'make
install' stage exits with the following error:

>No theme index file in '/usr/share/balsa/hicolor'.
>If you really want to create an icon cache here, use --ignore-theme-index.
>Failed to write cache file: Permission denied

The permission denied is relatively normal (I'm purposely not
installing as root), but uhh... *where* does it want to put the cache
file? Is it possible to get any more detail about what it's trying to
do?

--
Lennon Victor Cook