I see that in the default templates, there are things like this (rssitem.tmpl):
-<TMPL_IF AUTHOR>
+ <TMPL_IF AUTHOR>
<title><TMPL_VAR AUTHOR ESCAPE=HTML>: <TMPL_VAR TITLE></title>
<dcterms:creator><TMPL_VAR AUTHOR ESCAPE=HTML></dcterms:creator>
-<TMPL_ELSE>
+ <TMPL_ELSE>
<title><TMPL_VAR TITLE></title>
-</TMPL_IF>
+ </TMPL_IF>
But I don't get this in my RSS, and I don't know how to add those variables, except for mentions of some plugins that are not yet merged.