Icon for double line at bottom of cell.

[D Garing]

I placed a separate icon for this on my toolbar, but when I use it I only get
one line at the bottom of the cell, even though the icon itself shows it
should put two lines at the bottom of a cell.

When I use the icon within the group of icons for lines within and around
cells (a group of 9 within the dropdown arrow) it puts the double line at the
bottom of the cell.

Is this a program flaw or is there something I can do to get a separate icon
for two lines at the bottom of a cell.