Grid group by column using xml

How can columns be grouped using XML? I found this page, which explains how to do it using setHeader, but that doesn’t seem to work with an XML configuration.

The format is absolutely the same:

<column width="60" type="ed">{#collapse}2:text</column>

I’ve just checked, and it works well for me locally.

Thanks. It wasn’t obvious how to do that with XML. Your example helped a lot.