I've done the usual edit of /etc/sysctl.conf to include the parameter, but it just tosses errors. I haven't had to tune a kernel in a very long time, what's different about it nowadays (or have I simply forgotten how)?
edit:
Added "kernel.semmni = 2048" to the tail of /etc/sysctl.conf and then ran "sysctl -p". End result is an unknown key error (apparently kernel.semmni isn't the valid name anymore?).