I think it's better using css instead of message keys, for several reasons. One point not mentioned yet is that we could define similar mime-type icons in one line, using the same configuration, for instance:
.mime-type-doc, .mime-type-docx, .mime-type-txt {
background: url(/acs-lang/resources/images/mime-types/doc.png);
}
I recommend using a self-explanatory class name, for instance: mime-type-blablabla. Sample:
...download a <a href="../blabla/file.zip" class="mime-type-zip">zip version</a> of this folder...
You could also define a css style using "css attribute selectors", in order to put a spanish flag in every explicit spanish link. Something like that:
a[lang=spanish] {
background: url(/acs-lang/resources/es.gif);
}
if you had something like
<a href="@url@" lang="spanish">
Anyway, there is one question I have found: How could we mix 2 icons (i.ex. for a spanish zip file)?