Let's first learn about how the different formats are registered with the web script framework. If you take a look at the bean entry with the ID as webscripts.formats in spring-webscripts-application-context.xml in spring-webscripts-*.jar, it has the entries for formats and MIME type corresponding to the available formats. The org.springframework.extensions.webscripts.FormatMap parent class for this bean definition entry, webscripts.formats, registers the formats and MIME types with FormatRegistry used by the web script container in the web script framework. In order to add custom formats, all you need to do is provide the appropriate format and MIME type entry. If you take a look at the bean ID, webscripts.formats.IE in spring-webscripts-application-context.xml, and its customized entry in web-script-application-context.xml, it has defined the custom IE specific formats. It has changed the format for rss from text/xml to application/rss+xml. Similarly, you can...