After having an extra look, there is a ConfigurationOfXMLSupport in my image (coming from Seaside 3) which reads:

baseline120: spec
<version: '1.2.0-baseline'>
spec
for: #common
do: [�
spec
blessing: #baseline;
repository: 'http://www.squeaksource.com/XMLSupport'.
spec
project: 'XML-Writer'
with: [�
spec
className: 'ConfigurationOfXMLWriter';
repository: 'http://www.squeaksource.com/XMLWriter' ];
package: 'Collections-OrderPreservingDictionary'
with: [ spec repository: 'http://www.squeaksource.com/OrderPreservingDict' ];
package: 'Collections-BitmapCharacterSet'
with: [ spec repository: 'http://www.squeaksource.com/BitmapCharacterSet' ];
package: 'XML-Parser'
with: [ spec requires: #('XML-Writer' 'Collections-OrderPreservingDictionary' 'Collections-BitmapCharacterSet') ];
package: 'XML-Tests-Parser'
with: [ spec requires: 'XML-Parser' ].
spec
package: 'Opax'
with: [�
spec
repository: 'http://www.squeaksource.com/OPAX';
requires: 'XML-Parser' ].
spec
group: 'default' with: #('Core');
group: 'Core' with: #('XML-Parser');
group: 'Tests' with: #('XML-Tests-Parser') ].
spec
for: #squeakcommon
do: [�
spec
package: 'Pastell'
with: [�
spec
requires: #('XML-Parser');
repository: 'http://www.squeaksource.com/Pastell' ] ].
spec
for: #gemstone
do: [�
spec repository: 'http://seaside.gemstone.com/ss/XMLSupport'.
spec
project: 'Grease Core'
with: [�
spec
className: 'ConfigurationOfGrease';
versionString: '1.0.3-baseline';
loads: #('Core');
repository: 'http://www.squeaksource.com/MetacelloRepository' ].
spec�
package: 'Collections-OrderPreservingDictionary'�
with: [
spec�
file: 'Collections-OrderPreservingDictionary.g';
repository: 'http://seaside.gemstone.com/ss/PharoCompat'].
spec package: 'SIXX' with: [
spec�
requires: #('XML-Parser' 'Grease Core');
repository: 'http://seaside.gemstone.com/ss/SIXX'].
spec
package: 'XML-Observable'.
spec
package: 'XML-Parser' with: [
spec�
file: 'XML-Parser.g'].
spec
group: 'Core' with: #('XML-Observable');
group: 'default' with: #('Core') ]

And obviously picks things up from squeaksource...

Damnit.

Phil