I have problem. one of my site is being hit by google bots and msn bots ... this thing makes mysql connections go boom and finally all websites that use mysql go like: too many connections to sql bla bla ... any idea how to limit nr connections to mysql and to apache per ip ? like ... 4 max connections per incoming ip ?

You'll have to use mod_throttle for this purpose..

BTW, for MSN-Bot you can set Crawl-Delay: 5 or even 10 in your robots.txt file to make it crawl slowly.