T3D 1.1 Beta 3 - obj-disableCollision() causes obj to disappear ? - LOGGED

Hello, I don't know if this is wanted but I extended the vehicle class to create an obj of my own. Now I want that this obj passes through the other objects so I used this->disableCollision(); in the constructor.
The obj collision is disabled but also isn't visible !! If I reenable the collision the object reappears !! Is this normal or a bug ?

Thank you !!