I'd like to replace some HTML form pages with XHTML pages containing XForms, but I need to know how to deliver XForm capabilities to end user Web browsers. The server-side pre-processing tools seem cumbersome, and we don't like the idea of requiring users to download an XForms rendering plug-in. Are those the only alternatives available for delivering XForms to existing browsers?

The FormFaces XForms processor is a pure JavaScript solution to the problem of delivering XForms-rendering capabilities to Web browsers.

FormFaces is available under a dual licensing model, through which you may acquire either the software under the GNU Public License for open source use or purchase a commercial license for proprietary development.

Including the formfaces.js JavaScript file in your Web pages provides XForms-processing capabilities for existing browsers. The latest update provides the ability to load model instance data from external sources; a full XPath implementation; and reasonably complete support for the XML events framework, the set of XForms events defined by the XForms 1.0 specification.

The FormFaces documentation includes an XForms-compliance matrix showing exactly what is and is not supported, along with numerous test forms and a bookstore application demonstrating the use of XForms' repeating groups, calculations, relevance and data-validation features. FormFaces may be the cross-platform XForms rendering solution you are looking for.