Anyone here seeing the AFP load issues many Leopard Server admins are seeing?

There's a massive discussion on it over at Apple Discussions. Many saying they've got AppleCare cases logged. I've got a customer who has one logged too. May only affect high impact servers, such as those in high school environments with hundreds of Mac and PC clients. AFP swaps the CPU allowing nothing else to operate normally. This results in all sorts of problems at the client end from login failures to slow saves. It essentially brings the entire school down. It almost looked like the recent Security Update was going to fix this, as it referred to a race condition, but sadly it hasn't helped.