Personally, I prefer VASSAL to Cyberboard since it offers greater flexibility. And if anybody here uses VASSAL there is already a module for "A Call to Arms" although it isn't complete. It's available under the modules on the VASSAL website.
For those who aren't familiar with VASSAL it is a JAVA based gaming system available at www.vassalengine.org. Like Cyberboard it's free and can be used for online face-to-face play, play-by-email and offline play as well.
