I would, but the links to Sharepoint are of the format "
https://sharepoint-server/download.aspx?file=bla.docx". Dokuwiki treats that as aspx for the purposes of icon generation :(
Edit: Sorry, Andi, I meant to say thanks, I didn't realise I could use media syntax and eagerly tried it out. That's when I discovered the above, which I guess means that I'll have to write a plugin anyway, either to alter external link rendering, or to change the way media syntax parses querystrings.