Asking for a simple XML of categories hierarchy

Hello,

I'm developing a web site, and I need only the categories hierarchy with the names of the catagories, without any additional information from the dump.
I'm looking for a ready XML, or an easy way to edit a XML, that will look like the following example:

<xml>
..<category>Arts</category>
....<category>Painting</category>
......<category>Oil</category>
......<category>Ink</category>
....<category>Drawing</category>
......<category>a</category>
......<category>b</category>
..<category>business</category>
....<category>Accounting</category>
ETC...
</xml>