It stops lots of things from what I've seen. Devices that are connected to the switch will continue to function, but if you plug in a new device you don't get a link light or anything. Very strange. Power cycling it fixes the problem for a day, week, or month. That gets old especially in an environment running two shifts and no way to access the switch remotely to cycle it.
I didn't even bother opening a support case with Avaya for the issue because I knew what the answer would be. I do need to get back to that customer and zap them up to 5.0.2 and see if it cures it. If not then I'll open a case and send logs and get put in the "wait for next release" queue.
Lots of folks on here bash Nortel, but their support for the data products was a lot better than the way Avaya handles it. I remember back when you'd call in an issue, get a real engineer on the phone working with you to figure out what was happening and get a new build in a day or two. Now it's logs, sniffer captures that show absolutely nothing relevant and waiting for days or weeks to get an answer.
Sorry for going off on that tangent.