<fo:root xmlns:fo="http://www.w3.org/1999/XSL/Format" >
     <fo:layout-master-set>
          <fo:simple-page-master master-name="test-page-master" page-width="8.5in" page-height="11in">
               <fo:region-body margin-top="0.4in"/>
          </fo:simple-page-master>
     </fo:layout-master-set>
     <fo:page-sequence master-name="test-page-master">
          <fo:flow flow-name="xsl-region-body">
               <fo:block font-size="10pt" line-height="12pt">This is a paragraph that has a
                    <fo:inline border-left-width="12px" border-style="solid" padding-left="2pt">very long span in it, and the span has a 12px border separated from the span by 2pt of left padding (the difference between the line height and the font size), which should overlap with the lines of text above and below the span, since the padding and border should not affect the line height. The span's border should have vertical lines only at the beginning and end of the whole span, not on each line.</fo:inline> The line spacing in the whole paragraph should be 12pt, with font size 10pt.
               </fo:block>
          </fo:flow>
     </fo:page-sequence>
</fo:root>