filtering and Windows XP

[L Parry]

We have been using Fortress and Cyberpatrol on some of the library public
access computers for over a year without problems.  The latest replacement
computers have come in with Windows XP as the operating system.  Both
Fortress and Cyberpatrol appear to install; however, if Fortress is active,
Cyberpatrol does not work.  (It appears to be active, but does not filter).
 The explanation I have gotten from another staff person is that XP will
allow only one filtering program at a time to operate.   Is this a general
problem, or is there a simple work around that I am missing?  Any
suggestions would be welcome.
L Parry, Electronic Outreach Librarian
Wicomico County Free Library
P.O. Box 4148
Salisbury, MD 21802