Just got a link to this blogpost from Micheal Widenius a.k.a. Monty. Yes, the founder and orignal developer of MySQL who recently left Sun. He is telling the world that the 5.1 wasn’t ready for a GA release and that you should be carefull if you use it.
I’ve only installed it on my test server for the moment. I would suggest you do the same and not use it on a production environment untill the dust has settled on this. I will try to keep following this to keep you informed.
I will still write the installation document for 5.1 but it will be on your own risk if you want to use it. I hope this problem will be worked out soon.