mysql in production on freebsd 6.1 ???

[ke han]

I need feedback from users with mysql 5.0.x (or even 4.1.x) in  
production on SMP systems. X86_64 Opteron is my platform.
I have heard rumors of it not scaling and it crashes and odd errors   
Have these been worked out in the latest releases of freebsd and mysql?
Any thoughts on this topic may help me substantially.
If you cannot provide info publicly, private replies are fine...I  
just need some production level feedback.
thanks, ke han