Funny intersections

I seem to be getting these a bit lately, and I’m not sure if it is just the project / file I am in, or something in v6, but I am getting surfaces that don’t intersect the way I would expect. In the attached, try projecting the curve onto the surface in the top viewport. You will see that although the curve to be projected runs well past the surface, the projection does not, thus trimming fails.

Thanks,
Sam

NoTrim.3dm (176.6 KB)

Same thing happens in v5. I’ll put it on the bug list. Thaks,
Chuck