Got this from a good source @ novell. Obviously this is just an FYI,
take it or leave it..

I would suggest holding off on deploying SP5 for a few months ... or at
least until I can email you back again. We're chasing a few interesting
issues that I would prefer you not run into after deploying SP5.

We're seeing some interesting timing issues ... windows if you will ...
that we hadn't seen before and are causing problems in areas that we
didn't know had problems. How's that for being vague?

These timing issues do not affect every customer running SP5; rather,
just a select few. Most of the problems have been seen with NLDAP/DS
and a few OS monitoring type functions.

We're just at the beginning of tracking this one down. I'll let you
know when we've finally got a handle on this.