Added object invisible?

Hi everyone, i am currently working on a “dynamic networking” setup in blender.
Don’t worry, its not the networking that doesn’t work!TEST3.blend (438 KB)
The problem is, when i try to position the object, it suddenly becomes invisible. Only when using either ob.position or ob.worldPosition
:@

print worldPosition afterwards to see where it has gone?

Hmm. It is worse than i thought.
It is positioning. I just can’t see the added object :@

try changing the visible flag?