This would be a nice feature. In the meantime, here's the maths you need.
When A collides with spinning B and you want A to stick on to B, first calculate the distance and angle offset from B to A and store these in private variables, eg.
Set 'dist' to distance(B.X, B.Y, A.X, A.Y)
Set 'ang' to angle(B.X, B.Y, A.X, A.Y) - B.angle
then, from then on, always set A's X and Y co-ordinates to
B.X + cos(A('ang') + B.angle) * A('dist')
B.Y + sin(A('ang') + B.angle) * A('dist')
I can't check this works right now but its the right idea. Some kind of 'Stick' feature would definitely be useful instead of this though.