I'm currently running version 3.2.0, and the cgi refresh rate is configurable in the cgi.cfg file:
# REFRESH RATE
# This option allows you to specify the refresh rate in seconds
# of various CGIs (status, statusmap, extinfo, and outages).
I don't recall seeing this in version 2.x though, so it depends on the version of your install.
Hope this is what you were looking for.