Baking textures and borders


I am facing the same problem for couple of years now.
Why when I bake textures (or ambient occlusion) I get that strange looking borders where meshes come together?
These pics shows it all:

What am I doing wrong?

and have a nice day. =)

it looks like a face overlapping problem… perhaps you have to change the topology a bit, or try to ‘remove-doubles’…

Removing the doubles did not solve the problem.