Connection issues with Microsoft Freelancer when using NAV and Microsoft Vista

When using Norton Antivirus 2009 in Windows Vista Ultimate, I am no longer able
to connect to multiplayer servers in the game Freelancer.  I can still see the
servers in the multiplayer list, but a connection cannot be established.  There
are no virus alerts, and the security history does not show any activity from
NAV that would prevent connection.  Additionally, preventing NAV from activating
at startup does not resolve the connection problem.  However, uninstalling NAV
does correct the issue, but I would prefer a solution that allows me to continue
using this Antivirus software.
It should be noted that using NAV 2009 in Windows XP does not have this issue,
it appears to be the combination of NAV and Vista.
This is a well spread issue in the Freelancer community among several different
Antivirus softwares, with the only solution being to completely uninstall the AV, but this
simply is not an option I would prefer.  Any assistance would be much
appreciated.