If the top, bottom, and right borders of all elements above match, then this passes test.


li   { border: 1px dotted magenta;
       margin: 10px 0; }  /* spreads out the elements for better border viewing */

li.a { border-left: 1px solid orange; }
li.b { border-left: 2px solid lime; }

When a 2px or greater is defined for a list element's border (any side) -- as demonstrated in class b -- IE7b2p renders dashed borders. This is actually an improvement over IE6 that never renders 1px dots.