There are 3 multi-ship solutions available that a host can run, however they're not very popular and I haven't run one here for quite a while.
You have the original one called The Killing Floor by Dale Pope.
Another was created by Kenneth Strom called Tactical VCR 2 which was a little better than TKF.
Each of these required modifications to be done by the host when the game was setup and for the player to each have a plugin they used on their side as well.
Most recently a new multi-ship combat solution was created by Stefan Reuther called FLAK which is for PHost, not Tim's VGAP. PHost is similar to Tim's game but different and in may ways more advanced.We run PHost games here as well and ran a test game for FLAK a year or so ago. Stefan is also the Author of PHOST and the PCC player client that can be used with Tim's VGA Planets as well PHost.