When you open IDE and plug-in is active it connect periodically to
subversion server(s) to check availability of connection. This is need
maintain correct functionality of plug-in depending on your on-line or
off-line status. This behavior controlled by plug-in option "Determine
on-line/off-line status".
If you switch off this option plug-in should _not_ connect to any servers
except when required (you make check-in, check-out etc).
The log records that shows that plug-in connects to non subversion servers
you use I consider erroneous.
On our experience we know several compatibility or other issues with zone
alarm. I advise you to use another firewall "outpost firewall" -
http://www.agnitum.com/. At least use trial version to check that svn_svn
really not connect to any servers except subversions servers you use.