If permissions for "/" are (1341/d-wxr----t) clamsmtp insists at start that: clamsmtpd: couldn't open pid file: /var/run/clamav/clamsmtpd.pid: Permission denied even when /var/run/clamav/ is owned by "clamav" user & group with correct perms, clamsmtp will not write its pid to file in this directory and ofcourse its stopping by initscript is impossible. It will not work at all as it also insists that it have denied permission to clamav socket which is also in /var/run/clamav directory. Setting "/" perms to o+r helps but sucks ;)
Experimenting with filesystem permissions in such way, you are basically on your own.
Try to report this upstream, but there's nothing we can do with this issue.
