colada and extra mesh

I created an importer of skin mesh from COLLADA.
The problem is that I have a soldier with a sword or a killer with a gun.
I’m import The mesh of the sword and gun , but just i not know how to animate they because they are not bone.
the question is this:
I must use these mesh as with a normal bone or with a keyframe animation?
if I have to animate with keyframes, how do I? I have a set of matrices for each unit of time (every 1 / 30 of a second),
how do I use these matrices?
Thank you.