The port should be opened by javaw.exe, but I suppose you know that.
I just noticed that the updater does not appear to support proxy servers. The proxy info I enter into the control panel applet is just ignored. When I supply the proxy information manually via the command line it works:
javaw.exe -Dhttp.proxyHost=PROXYHOST -Dhttp.proxyPort=PROXYPORT -jar Updater.jar
Kaldran, start fixing the network code of Java.
