[calorie]

Go to AdminCP >> Styles & Templates >> Style Manager >> select Main CSS from the dropdown menu >> scroll to the very bottom, and in the empty box under the Additional CSS Definitions section, add the following CSS:

a:link span
{
	color: #FF4400; text-decoration: underline;
}
a:visited span
{
	color: #FF4400; text-decoration: underline;
}
a:hover span, a:active span
{
	color: #22229C; text-decoration: underline;
}

Now use <span> </span> in AdminCP >> Usergroups >> Usergroups >> Edit Usergroup >> Username HTML Markup. Note that the links should be #FF4400 orange and, when you mouseover the links, they should be #22229C blue.