This item is to track adding better support for change tracking with graphs of disconnected entities. For more information see this discussion:
"Merge Disconnected Object Graph"
http://entityframework.codeplex.com/discussions/432661
And this user voice item:
"Merge method: automatic synchronization of relationships on a disconnected entity"
http://data.uservoice.com/forums/72025-entity-framework-feature-suggestions/suggestions/1069431-merge-method-automatic-synchronization-of-relation
Comments: Please see http://refactorthis.wordpress.com/2012/12/11/introducing-graphdiff-for-entity-framework-code-first-allowing-automated-updates-of-a-graph-of-detached-entities/ and the code here at https://github.com/refactorthis/GraphDiff. This should solve your problem.
"Merge Disconnected Object Graph"
http://entityframework.codeplex.com/discussions/432661
And this user voice item:
"Merge method: automatic synchronization of relationships on a disconnected entity"
http://data.uservoice.com/forums/72025-entity-framework-feature-suggestions/suggestions/1069431-merge-method-automatic-synchronization-of-relation
Comments: Please see http://refactorthis.wordpress.com/2012/12/11/introducing-graphdiff-for-entity-framework-code-first-allowing-automated-updates-of-a-graph-of-detached-entities/ and the code here at https://github.com/refactorthis/GraphDiff. This should solve your problem.