In one of our dreams, we can build a highly custom CMS out of independent Java components. Well, at least part of that dream has been reality for some time: you can get fairly good standalone and embeddable workflow engines and plug them into your existing J2EE architecture. We've previously highlighted Oak Grove Systems; you might also want to check out Dralasoft, who are partnering with repository component vendor, Xythos. Don't let all their "Business Process Management" verbiage fool you. These are straightforward workflow tools, and both are already getting OEMed into commercial CMS packages...
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