[Mediawiki-l] Different URL path for different namespace?

Kind of a newbie question... I'm not even sure of the appropriate taxonomy for my request, maybe that's why Google didn't help.

Using last stable (1.16.2 I believe), I'm trying to achieve this:

Got a default setup, Mediawiki installed in /w, Apache conf edited with an Alias. So now my wiki is accessible at http://domain.tld/wiki/

I would like to link a specific namespace (let's say "bar") to its own URL, outside of /foo/.

Ok, to rephrase, hopefully better:

I would like: domain.tld/wiki/Bar:SomePage to be in fact: domain.tld/Bar/SomePage

And if Apache could rewrite on the client side /wiki/Bar:SomePage into /Bar/SomePage that would be even better, albeit not a deal breaker.

Without breaking anything in MW of course. And if the Recent or Search tool return the Bar:SomePage that's not an issue, I don't want to rewrite the MW core :)

Anyone got an idea?