You might want to also check out OpenInteract. It's
Template::Toolkit based but
offers a model for building more integrated portal-like
environments. I've been using it a bit but not really enough
yet to say too much about it. One thing I like is that it
has a built-in persistence/security model, SPOPS.
This allows you to build portal objects with different access permissions for different groups/users.
I'd like to hear other monks' impressions of OpenInteract if
there are any out there using it.