Hi everybody!
I am making an FPS, which is based at http://matter.x10.mx/about.php
I have a soldier model for my game, and it has been rigged.
My question is how to link the hands to the gun, and enable it weapon switching.
It has those ‘bone-things’ which move all the child armatures.
I am fine with python, but sometimes issues in the GE(such as Multiplayer) swamp me!
any contributions? 
The easist way is to parent the gun(s) to the hand and make the gun(s) on startup invisible. To see the gun(s) you only need to switch it to visible. Look at the blenderchookie video at minute 18:00 http://www.blendercookie.com/2010/06/09/game-engine-simple-character-part-3/.
ok, ill try that! thanks HG1; i had thought about trying that, but was wondering if there was a better way!
If you don’t want to do ist so, you can try to parrent a empty to your hand and add the gun(s) from an other layer. Then parent the gun to your empty. Here is a link to a game http://blenderartists.org/forum/showthread.php?t=143156&page=1&highlight=bullethole.