They do not have MaxClients set to 32000, go ahead and enable mod_status on one of your machines and drop MaxClients to 10, you'll still see 32,000+ dots. I did quite a bit of "searching" but I have yet to come up with a solid answer as to why there is 32,000+ slots showing other than that's just the way it is.
Out of curiousity is this an apache 1.3 server?
*edit* you may not see 32,000+ dots, but one of my machines reads like that and I have tried dropping all the setitngs down and rebooting apache with the same results.
I wouldn't be worried about it either way. To be honest with you I have yet to run a apache 2.x machine (good ole' 1.33 still running strong) on anything but a few test machines here at home, mod_status on them shows properly but they are not running directadmin
I would be willing to bet the reason they are showing the way they are is due to directadmin, but I can vouch for the fact that DA can hold up quite well under load.
Well you can try setting your httpd.conf setitngs to a very very low setitng, and you'll still notice no change in the mod_status scoreboard.
A better place to start would be reviewing what site sare getting the most traffic and what scripts are being called. Then working to optimize your server (mysql and apache mainly) to deal with those scripts better. This is assuming that the load is caused from a script and not a DDoS of course.