[Zope] Locked out of root ZMI

[Douglas Perry]

 I have an zope instance where I try to log into the ZMI and it won't accept
my password. The password has not been changed. I can log into other parts
of the ZMI where there a folders with their own acl_users folder. It just
fails when I try to login to the root ZMI. I'm running site root, OpenSSL,
Apache 1.3.22 as a caching proxy, and a few local roles in the intranet
folder (a CMF site).

Mozilla returns an error "intranet.company.com recieved a message with
incorrect Message Authentication Code"

Not too long ago, I packed the database.

Is it the caching proxy or some other cause?