[Zope] CoreSession + Non-undoable databases

[CJ Kucera]

I'm looking into CoreSessionTracking, and like what I see, but
I've got a question.

I want to have sessions persist beyond browser shut-off, which
means I'll need a Session Data Container.  In the docs, it's
mentioned that the Data Container should be instantiated inside
a non-undoing database.  Well, I want to keep the undoability
of the ZODB for most of my site, so how do I mount a 
non-undoable database somewhere in the tree?

I've looked around at zope.org, and I've run into MountedStorage,
but it seems to be out of date ("need a very recent CVS, the
2.2-pre releases aren't good enough," etc), so I'm wondering if
there's a better way, or at least a Howto somewhere.

Thanks again!
-CJ

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