Remote management

My tech person is having difficulty managing Win XP computers once they have been updated to SP2. He says that once they are updated the firewall is turned on automatically and then in order to manage them remotely we would have to touch each machine. This would be very difficult. Is the reason he can’t manage them remotely because of the firewall? If so is there a way to roll out the SP2 without turning on the firewall. We have our own firewall and our own virus protection.