They are from the borders defined in the site's default.css file

.MainMenu_MenuItem {
 cursor: pointer;
 cursor: hand;
 color: black;
 font-family: Tahoma, Arial, Helvetica;
 font-size: 9pt;
 font-weight: bold;
 font-style: normal;
 border-left: white 0px solid;
 border-bottom: white 1px solid;
 border-top: white 1px solid;
 border-right: white 0px solid;
 background-color: Transparent;
}
.MainMenu_MenuIcon {
 cursor: pointer;
 cursor: hand;
 background-color: #EEEEEE;
 border-left: #EEEEEE 1px solid;
 border-bottom: #EEEEEE 1px solid;
 border-top: #EEEEEE 1px solid;
 text-align: center;
 width: 15;
 height: 21;
}

.MainMenu_MenuArrow {
 font-family: webdings;
 font-size: 10pt;
 cursor: pointer;
 cursor: hand;
 border-right: #FFFFFF 1px solid;
 border-bottom: #FFFFFF 1px solid;
 border-top: #FFFFFF 0px solid;
}

Maybe I'm the only one who cares about this   But I still had lines even after the update to the CSS file.  I finally set the CSS to this:

.MainMenu_MenuItem {
 cursor: pointer;
 cursor: hand;
 color: #40592C;
 font-family: Verdana, Arial, Helvetica, sans-serif;
 font-size: 10px;
 font-weight: bold;
 font-style: normal;
 text-decoration: none;
 background-color: transparent;
 border-left: #F9D8DB 0px solid;
  border-bottom: #F9D8DB 0px solid;
  border-top: #F9D8DB 0px solid;
  border-right: #F9D8DB 0px solid;
}

Where the font is the green I wanted and the other color in the borders is the pink.  So - now, I suppose the lines are still there, but they're pink so you can't see them.   I'm not sure what worked -- the 0px or the pink - but I can tell you that setting the borders to transparent did NOT work - the lines became green like the font.  That's how I figured out it was this particular style that was causing the lines.  -- this is the only style in my CSS that uses green.  

So, now, I feel like I "tricked it" into "appearing" to work - I still don't understand why the lines are there.  At any rate - the submenus look the way I want them, so I'm moving on.

Cathy
CoolCoyotes