If you put in something such as undefined tags or mismatched tags in .mdwn file, ikiwiki will put <p></p> around them. But ikiwiki will NOT convert < and > to &lt; and &gt;!
some text
the output html

some text

And another example of mismatched tags:
some text
The out put is:
some text

> This is a bug in markdown. Actually, not converting `<` and `>` in tags is a > markdown feature -- markdown allows inserting arbirary html, even if it's > made-up tags. And putting paragraph tags around your `
` tag is > understandable, since markdown can't know if `
` is intended to > be a block-level tag or not. The bug is that it puts the `

` around the > trailing `

` -- it does know what a div is, and it should know that's > illegal and not do it. I've filed a [bug report](http://bugs.debian.org/459269) about that issue > alone. If you feel the other things you brought up are bugs, please talk > to the markdown maintainer. --[[Joey]] [[tag done]]