[Dovecot] [dovecot] INDEX variable and mbox_snarf plugin

Is there a way to tell the dovecot mbox_snarf plugin to use an alternate location for the index/cache files? It doesn't seem to want to use the INDEX variable. I'm guessing the answer is no because of all the ties in lib-storage/index/mbox/*c to the directory where the file(that is the inbox) lives. The filesystem where I keep the inbox file doesn't have a directory for the user to own. The user only owns the mbox file.

Thanks, Jonathan