Poser can load motion from BVH files. However it seems to only load the 
joint angle data, and leave the skeletal dimensions untouched. This can
cause problems when the motion is played on characters with different
dimensions. For instance the feet of the character go through the floor.
I'm looking for a way to also load the skeletal bone lengths.
In theory this would be done by scaling the length of each segment and all 
the geometry attached to that segment. I believe Poser has all the right
capabilities built in, but the default import function does not appear to 
'do the right thing'. Can anyone point me at an import routine or script
that can do this? That is, a way to load not only the joint angles, but
also the bone lengths, so that the correct motion is preserved.

Poser is a commercial animation tool. I also have the 'propack' which
provides scripting and may be an important component in a solution.

BVH is just one format for motion capture data and happens to be the
one supported by poser natively. I would be willing to consider alternative
formats if they correctly load the pose of a character.

Thanks.