Export Blender cloth-simulated animation to Source

I made a cloth-simulated flag in Blender.
How can I export the baked animation to Source, since it has no skeletal animation?
I’ve been working with Blender and Source for a while, but I have few experience in porting stuff.
I read something about Flexcontrollers, but I have no idea what they do and how to use them.

Does anyone have experience with this?
Any help is greatly appreciated…

I don’t think that is going to be supported in Source, unless you give the flag an animation or a jiggle bone.

Yeah, I want to bake the animation, then port it to source.
I know source doesn’t support actual cloth-simulation, sorry if I wasn’t precise enough…

I think SFM does allow for vertex animations just not sure how to get them into the compile.

I was able to convert it to a .dmx-file, but I have no idea how to compile it. Even if I would, I doubt it would work with Source 2009.
I’m currently working on adding a sh*tload of rigs to the mesh, to be able to export it as .smd…