As Jordan says, tag formatting may be an issue but it may also be time to consider migrating away from original dirCaster (are you using v0.4 or earlier?) towards one of the new scripts built upon its foundation.
For example:
betdircaster -
<http://workingpathways.com/software/betdircaster/>
and another mod -
<http://www.nothingtodeclare.com/stories.php?story=05/04/19/0538021>
...
I've been hearing a growing number of, not so much complaints but concerns about dirCaster behaviors. The author is apparently still actively producing new iterations but his site isn't especially forthcoming (I don't believe he posts a working download link to the script there, or even an email address) so it may be time to consider alternatives for tweak supportability.
Also.
No doubt, you're already aware of this but just in case...
Podcast Alley's page listing popular podcast creation scripts and widgets:
<http://www.podcastalley.com/forum/links.php?id=14>
.d.