[ODE] re: trimesh woes

[Ian McMeans]

I've got a new problem, unfortunately. It seems like my trimeshes (no 
matter what the mesh data is, even a simple tetrahedron) hover a short 
distance above the box they should be resting on. And the distance they 
hover depends on the size of the trimesh, and the orientation (what I 
mean by that is that the "jet" (the fish-shaped- thing) can balance on 
its nose, but when I try to have it rest on it's side, it rests a 
distance above the box.

http://img23.exs.cx/my.php?loc=img23&image=problem.jpg

So I thought maybe the trimesh data was bad, but when I draw the 
collision data like this:
glBegin(GL_LINE_LOOP);
    for (int i = 0; i < totalTriIndices; i++)
    {
        glVertex3fv(vertices[triIndices[i]]);
    }
    glEnd();

it looks the way I expect it to. The data is passed to ODE like this:
dGeomTriMeshDataBuildSimple(odeMesh, (dReal*) vertices, totalVerts, 
triIndices, totalTriIndices);

Anyone have any ideas what's going on? This doesn't happen with box 
geoms, but it happens when I hard-code the trimesh data for a cube. I 
don't understand what could be going wrong.

Ian