If you try to select a template when creating a page on Internet Explorer 6 in the wiki markup tab (whether it is the default or not) a JavaScript error is thrown. Selecting the rich text tab and trying to select a template again works.

This only occurs when ISO-8859-1 has been set as the character encoding for Confluence. If it is UTF-8, saving works.

This seems to be independent of the database encoding (it was originally uncovered on an instance with the DB encoding set to latin1).
It also seems to be independent of the browser encoding setting.

Switching to rich text mode allows the user to select the template.
FireFox 1.5 doesn't seem to suffer from the same problem.