.defaultSkin span.mceIcon.mce_insertnewtab {
    background: url(../img/inserttab.gif) no-repeat top left;
}

.defaultSkin span.mceIcon.mce_insertclosetabs {
    background: url(../img/closetabs.gif) no-repeat top left;
}


.mce-i-inserttabs:before {
    font-family: 'campusnet-icons' !important;
	content: "\e908";
}

.mce-i-closetabs:before {
    font-family: 'campusnet-icons' !important;
	content: "\e907";
}