Strange theming bug on teasers

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Senpai's picture

When teasers are shown in either node/add/preview mode or as a post on the group's homepage, the table tag seems to break something in the input filters, regardless of whether the node is set to Markdown or No Markdown.

See the top stickied post at http://groups.drupal.org/san-diego (The full node is http://groups.drupal.org/node/18022) When displayed as a teaser, it breaks, but when viewed as a full node, it's fine. the HTML doesn't seem to be broken, so I have to assume that it's the node tpl?