Heh, hi lorax.
I don't think in this case it's about cloaking because Mobile user agents get a dynamic version of the site, why wouldn't Google get one too? In the end visitors and google see the same thing. I can only offer a cached version of the site to visitors because I have heavy traffic and my server would die in ~ 10 minutes. I don't think it's wrong, I don't intend to do anything blackhatish :)