The syntax for pasv-allow and port-allow seems to be wrong in ftpaccess(5)
man page.

It says:

port-allow <class> [<addrglob> ...]
pasv-allow <class> [<addrglob> ...]

This should be:

port-allow <class> [<cidr> ...]
pasv-allow <class> [<cidr> ...]

To duplicate, if you put something like:

port-allow all *
pasv-allow all *

in /etc/ftpaccess, ftpd will die with SIG11.

On the other hand this works:

port-allow all 0.0.0.0/0
pasv-allow all 0.0.0.0/0