[[!comment format=mdwn
 username="http://jmtd.livejournal.com/"
 ip="188.222.50.68"
 subject="comment 2"
 date="2011-05-23T18:51:41Z"
 content="""
You haven't followed the examples properly. The code fragment needs to be inside `code=\"\"`, i.e. `[[!teximg  code=\"\frac{1}{2}\"]]`

(taken directly from [[ikiwiki/directive/teximg]])
"""]]