KineFX: How to use Look At with Skeleton Mirror?

[raincole 2]

When I try to apply Look At constraint on a joint that is mirrored by Skeleton Mirror SOP (Mirroring Style: "By Scale"), it's completely broken:

 

The same Look At works when Mirroring Style is "By Rotation":

 

But I've already had way too many non-procedural keyframes and I really can't change Mirroring Style at this point. Is it possible to make Look At work for joints that are mirrored by scale?

Edited March 25 by raincole