You define a class for your menu and then put its name into the Addition Class parameter inside your menu configuration.
and here is the class applied for the home menu:
/* Special Buttons */
#ja-mainnav li.home { }
#ja-mainnav li.home a.home {
padding: 4px 0 3px;
margin: 3px 5px;
text-indent: -1000em;
width: 28px;
}
#ja-mainnav li.home .childcontent-inner { background-position: 14px top; /* Realign The Arrow */ }
span.has-image {
min-height: 18px;
}
/* Home Button */
#ja-mainnav li.home a.home { background: url(../images/icons/home.png) no-repeat center !important; }
#ja-mainnav li:hover a.home,
#ja-mainnav li.over a.home,
#ja-mainnav li.active a.home {
background: url(../images/icons/home-l.png) no-repeat center #000 !important;
}
you can replace ‘home’ by your class and use other icon for this
