Mail Security and Locking Problem

[joe at teltone.UUCP]

Since you have solved our news problem I thought I would try the problem we are 
having with mail.  We are running a semi-private mail system with the
following protection:

    d--x--x--x 2 root       1264 May 25 07:20 mail

    ./mail:
    total 342
    -rw--w--w- 1 aaron      1172 May 22 17:28 aaron
    -rw--w--w- 1 alex        342 May 24 13:39 alex

There are two intermitent problems associated with mail.  One is that
if two people simultaneously send mail to the same receipient the two
message are intermingled in one mail message.  For some reason the
mail locking mechanism is not working.  The other problem is that 
occasionally the file permissions are changed to

    -rw-r--r-- 1 alex        342 May 24 13:39 alex

This occurs more frequently if the mail directory has permission

    d-wx-wx-wx 2 root       1264 May 25 07:20 mail

I expect that there is a simpler way to have private mail and a more
secure way also.