Importing fbx animation files error Human animator has a generic animationclip()

I'm trying to import .fbx files into Unity 4.0 which I've created via various programs from original bvh source files. However although some work most of them produce the error:

Human animator has a generic animationclip() with animation on human transforms animation on those transforms will be discarded

I've tried to track down differences between the skeletons etc on the files but can't work out what it is. Any hints please + can we please a have a bvh importer

 

I've now solved the problem - I wasn't setting rig to humanoid for every imported fbx asset. doh

But please can we still have a bvh importer

 

thanks Joe

I've now tried importing 5 more .bvh files from you set via Fragmotion to turn them into .fbx files and they're loading straight in to a variety of avatars with no problems - Unity guys this new feature really rocks!!