I'm having a problem styling SOLPARTMENU.

I have rootmenuitemactivecssclass working.  Worked exactly as expected and took 2 minutes.

But I'm using the same technique for rootmenuitemselectedcssclass and it's not working.  I expect to see the effect of rootmenuitemselectedcssclass when I hover over a root item in the menu.

Here's an excerpt from the portion of my skin.xml file where I declare settings for SOLPARTMENU:

     
        rootmenuitemactivecssclass
        LeftMenu_RootMenuItemActive
     
     
        rootmenuitemselectedcssclass
        LeftMenu_RootMenuItemSel
     
 

And here's a corresponding excerpt from my portal.css file:

.LeftMenu_RootMenuItemActive {
    color: #002AFF;
}

.LeftMenu_RootMenuItemSel {
    color: #002AFF;
    text-decoration: underline;
}

Can anyone advise why rootmenuitemactivecssclass works but rootmenuitemselectedcssclass doesn't?

Thanks very much for any help on this.

Jim