I'm a bit confused now...

I'd like to replace the UrlBuilder completely. This is because I want a better url design, like forum.domain.tld/category/forum/subforum(s)/thread.aspx which I think this is better (maybe for my eyes only, but I dont want to have IDs in it).

It seems to be possible if setting "HttpContext.Current.Session ["YetAnotherPortal.net"]" to anything except null? Using this my assembly must have the name and type "Portal.UrlBuilder,Portal"?

Is this possible without modifying yaf source itself? Is anything like before, except url building (does login work, ...)?