Thanks to widening the team.space community, I found the problem for the Evil Ampersand problem about which I posted a couple of days ago. I found out that the problem was not so much an XML problem, but a problem about how team.sPace treats the values of the feed fields. For some reason I assumed that all values can contain XML data. Therefore, the ampersands in the contribution titles where handled as they would be part of XML strucutres. I fixed the problem by adding a very simple SAX filter that corrects the data strings so later processing can treat it as XML data chunks.