If one puts localized chars in wikilinks ikiwiki will escape it.
This works right from a technical point of view, but the URLs will become ugly.

So I made a patch which unaccent chars: <http://users.itk.ppke.hu/~cstamas/code/ikiwiki/unaccentpagetitlenames/>
This is a one liner change, but requires a bit of reordering in the code.

[[cstamas]]

[[tag wishlist patch]]