Not sure if this is a question Netware or Pmail

We are running the Netware NDS version of Pmail 4 on a Netware 5.2
server, with users Pmail folders held on the users' server volume. We
have recently had to implement disk quotas for some of our users but
have found that the Pmail folders appear to corrupt when the users
exceed their disk quota, eventhough they receive a message that their
user volume is full. It's not entirely clear which files are corrupt.

I wonder if anybody else has experienced this problem and has a
solution/work around. We are relunctant to shift the user mail folders
off the server since we have a comprehensive backup/restore procedure
for all server files.