I'm having a hard time visualizing what you mean. Is your problem that the mask moves with the layer?
You have a few options:
1. Animate the mask after animating the layer's transforms.
2. Duplicate the paint can, stick the globe precomp between the paint can layers, and use an Add mask on the top paint can layer to reveal the only parts of the paint can that should not be occluded by the globe.
3. Use a track matte instead of a mask to matte the globe over the paint can.
Principal & Designer at Keen Live
Motion Graphics, Widescreen Events, Presentation Design, and Consulting RenderBreak Blog - What I'm thinking when my workstation's thinking
Creative Cow Forum Host: Live & Stage Events