Well, I have about one third of a lot of x24c01 that will stop accepting
writes after 20 hours of use. No writes or reads during this 20 hour-time,
they just sort of "heat up" and stop accepting writes.

I am not writing during this time, I am not exceeding 100k writes (not even
100 writes), and  my routines are the ones XICOR recommends in their site. I
have also been using XICOR memories for years, without a problem. These
units (lot 9802) are definitely defective ones. I have tried to reach them
by e-mail (no reply), by phone (never a support tech guy there) left
messages, and never got a call back. They just ignored my efforts to talk to
them.

This lot is part of a product I make in Hong Kong, and we are in real
trouble, having to do a 24-hour burn-in before marketing the product, just
because of these memories. My partners are considering taking XICOR to the
justice.
I have not had a problem with XICOR memories before, this is the first time
I needed their support team help. To find there is none, at least for me.
Sorry if I sound angry.