box2d 007 - sticky polys!

hey guys,

im having a problem with circles getting stuck in polys which have been internally triangulated.
its also happening with polys sticking to other polys.
it seems to be occurring in particular when circles or polys collide at high velocities.
please see image below.

in the case of the circles getting stuck inside polys, it appears they sit between the gaps of the triangles.
was thinking that maybe this could be related to some rounding off error…?
not sure where to start looking if this is the case.

wondering if anyone else has experienced this and has a work around for this problem.