Technology and design in plain language.

This is more of a typo than a bug. When refreshing your default Main Index template, it pulls in the code from the default template directory of your MT installation, and the Main Index default template adds an additional `>"` to the link to atom.xml feed:

resulting in:

Removing the extra characters in the main_index.tmpl of your default_templates directory should take care of it no problem and ensure bug free template refreshing.