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WAServerAdaptor isn't really much like ring, rack et al.

Yes and no. It has the same responsibility in the "Seaside stack" but is "object oriented" and not "string/byte array oriented" and more high level.

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But it does put the thought into my mind that it would be interesting down the road to try and take the Seaside infrastructure and work something like rack into it.

Well the "problem" is that "traditional" servers (Comanche, Swazoo, OpenTalk) used to "object oriented" and fully featured web servers. Since building something like that takes a lot of work more recent servers (FastCGI, SCGI, AJP) are "string/byte array oriented". The later ones are obviously easier to adapt to a ring/rack/wsgi style interface.

a bit of background from me could help here. i'm going to end up having redline smalltalk using either netty or jetty be the final target for my own personal use of this when i'm done so the 'string/byte oriented' is going to be important to me. i'm playing around with how restful resources using stored blocks would look and the final end result i would build on top of it is going to be a combination of some stuff i wrote earlier this year in smalltalk using pharo ( ported to redline ) and a later part that i had a much easier time expressing using clojure. thus the jvm is a big + for me, but in general as i'm one of the redline guys, it is probably going to be my primary platform sometime in the future ( although i still love pharo and gemstone which i've used for a few years now and plan to keep contributing to in whatever fashion i can. )