CMS for managing plain-text content, with tagging

We have some quite-specific requirements for our app that a CMS may help us with, and were hoping that someone may know of a CMS that matches these requirements (it's quite a laborous task to download each CMS and verify this manually).

We want a CMS to allow users to create and manage articles, but storing the articles in plain-text only. All of the CMSs that we have looked at so far are geared towards creating HTML pages. We want the CMS to manage workflow (approval process), and tracking of history.

The requirements for plain text only is that the intent is to allow business people to generate content which we are going to display in our Silverlight application - we don't want to go down the route of hosting and displaying arbitrary HTML in the app as we want the styling to be seamless with our app, amongst other reasons.

We would also want to allow the user to be able to link to media stored on the server, but not to external sites (i.e. HTML with no formatting, or some other way of specifying article links), and the third requirement i开发者_运维知识库s the ability to tag articles and search on articles.

Does anyone know of any non-HTML targetted CMS systems that may match these requirements?

I would expect several CMS systems to allow this, but eZ Publish stores content as plain XML. And you have a way of allowing certain tags if you wish; and explicitly prevent for example external links. You then have options for how to present that content according the templates you choose to use.
You also have control via a /layout/set/myLayout directive. You could for example retrieve the content as a plain xml feed or a print layout or whatever custom format you choose at the time. With appropriate headers.

http://doc.ez.no/eZ-Publish/Technical-manual/3.10/Reference/Modules/layout/(language)/eng-GB

vs.

http://doc.ez.no/layout/set/print/eZ-Publish/Technical-manual/3.10/Reference/Modules/layout/(language)/eng-GB

You could define a layout such as /layout/set/xml/....

Workflow as in content approval processes, versioning, tagging and search are standard.

You can give Statamic a try.

http://statamic.com/

Not sure if you can disallow external links, though.