Event collide is only thrown once when stacked objects enter trigger

[ChrisAcrobat]

How to reproduce

1. Stack two Spheres on same position and collisionFilterGroup/collisionFilterMask them so they don't interact.
2. Add collide event listeners.
3. Add a Sphere-trigger.
4. applyImpulse so they move into trigger.
5. See that you only get a single collide-event.

Is it only me, or has some one else also encounted this?

[ChrisAcrobat]

I found my problem.
collisionFilterGroup default to 1 (first group) instead if -1 (all groups).
When I added a check to set collisionFilterGroup to -1 if it was unset everything started to work.