Last modified: 2008-06-10 17:38:48 UTC
According to FEED Validator, ctype="application/rss+xml" is served as "text/x-wiki"; see URL
application/rss+xml is not a safe type (as it may contain arbitrary HTML etc), and is not on the action=raw type whitelist. Thus it falls back to the default.
You're asking for the raw page content, which is text/x-wiki
Not all ctypes are allowed, in fact only a few.
Maybe you wanted to ask for whitelisting it/creating an equivalent feature?