Binding OData sub collection not working - binding

Question

Given the following data source (OData V2):
Types: Customer, Project, Customer have a collection of Projects
So /Customer is providing me a List of Customers,
Alike /Project
and /Customer(guid'xxxx')/Project is providing me a list of projects associated with the customer.
Now, given a View (List) on /Customer is showing me the customers. Having the routing set up so that selecting the individual Customer moves to a separate CustomerDetail View which shows details of the customer as well as its Project collection. Details of customer are shown perfect, I also get one row per Project, however, Project fields like name, description etc. are not shown in the list. Investigating further, clicking on a list item and thus invoking the event handler shows me that the list items have as BindingPath /[object Object] which is not what I expect.
Binding the List on /Project is working perfectly but shows all projects, not only those of the Customer.
To make things more complicated, when I add a new Project through a Dialog to the List (thereby doing a Create on the OData Model), I can see that there is a roundtrip to the server and the OPENUI5 is requerying the projects (using ' /Customer(guid'xxxx')/Projectinstead of the initial query with/Customer(guid'xxxx')?$expand=Project`. Then, the list is fully populated! Please note that all the time, there is no change in my binding, this is purely internal magic by OPENUI5.
The odata source provides as follows:
{
"d" : {
"__metadata" : {
"id" : "http://BASEADDR/Data.svc/Customer(guid'XXX')",
"uri" : "http://BASEADDR/Data.svc/Customer(guid'XXX')",
"type" : "CNTM.Customer"
},
"Project" : [{
"__metadata" : {
"id" : "http://BASEADDR/Data.svc/Project(guid'XXX')",
"uri" : "http://BASEADDR/Data.svc/Project(guid'XXX')",
"type" : "CNTM.Project"
},
"Id" : "XXX",
"CustomerId" : "XXX",
"Name" : "Noch eins",
"Description" : "",
"IsDeleted" : false
}, ...
],
"Id" : "XXX",
"Name" : "TEST",
"IsDeleted" : false
}
}
Customer includes Project Collection with multiple projects.
Binding on XML View is:
<Table items="{Project}">
The event handler on the item is:
onProjectItemPress: function (oEvent) {
var oItem = oEvent.getSource();
var oCtx = oItem.getBindingContext();
var gId = oCtx.getProperty("Id");
this.getRouter().navTo("project", {
projectId: gId
});
}
and the result in the console is
oCtx : constructor {oModel: constructor, sPath: "/[object Object]"}
I have been using this kind of binding approach already in other projects, but this rather trivial sample is really strange...any ideas?
Thanks, regards
Jörg Fischer