Calendar - differentiate-between-internal-and-external-links

[Mr_Running]

I have been using this for two years and I am wondering how to apply it to the Calender? see here

.postcontent a[rel="nofollow"][target="_blank"] { 	padding-right: 13px; 	color: #36B; 	background: url({vb:stylevar imgdir_misc}/external-link.png) no-repeat 100% 50%; }