I can mount /tmp/test manually with it:
sshfs email@example.com:/tmp/test /tmp/test
The relevant line I'm using in fstab goes like this:
firstname.lastname@example.org:/tmp/test /tmp/test fusefs.sshfs ro 0 0
but I am getting this:
mount: email@example.com:/tmp/test: Operation not supported by device
I get the same if I replace fusefs.sshfs with fuse and add sshfs# to the beginning of the line.
It should go something like
firstname.lastname@example.org:/tmp/test /tmp/test fusefs ro,mountprog=/usr/local/bin/sshfs,allow_other,late 0 0
Thank you, Tobias; the `mountprog' option did the trick.
While sshfs(1)'s manual page doesn't mention the need for this (and in fact incorrectly claims that mounting from fstab(5) is as simple as specifying `sshfs' as the file system type), that's a sysutils/fusefs-sshfs problem, so this base system bug can be closed.