For folks installing or upgrading to Adobe’s CS3, beware that installation of the Adobe Version Cue CS3 turns off your firewall and leaves it in that state.
It seems that a new rule is added to the firewall settings allowing TCP access to ports 3703, 3704, 50900 and 50901. Presumably, this is so Version Cue can download and install updates. However, in this process, the firewall gets turned off. It seems that the installation script fails to turn it back on after the installation is complete.
Check your firewall settings if you’ve recently installed Adobe CS3!