I have an existing Ecore model that I would like to modify. For modifying I would like to use Xcore. An answer to another question says, that it is possible to import classes from an Ecore model to an Xcore resource. However since I would like to change existing classes, this doesn't work for me.
Reading the eclipsepedia entry for Xcore nor searching the web didn't bring anything useful.
So how can I create an Xcore resource from an Ecore model?