QDesignerPropertyEditorInterface::propertyChanged() is never emitted - it seems from the code that this signal has been changed/renamed to QDesignerPropertyEditorInterface::propertyValueChanged()

Unfortunatelly, the QVariant parameter does not hold the expected (changed) property but some designer internal reference: qdesigner_internal::PropertySheetEnumValue

This should be reflected in the docs ... and the (unusable) QVariant should be changed to hold the expected value as explained in the docs (Qt-4.6.1/doc/html/qdesignerpropertyeditorinterface.html @see Detailed Description)

This is also mentioned in QTBUG-2744, but the topic is misleading