Client-side exception with a select tree in a repeat

Hello,

I have been trying to implement a simple select control with a xxforms:tree appearance inside a repeat, but it seems that I may have run into a possible bug in Orbeon XForms. Attached to this post you should find a simple XForms page which can be run in the sandbox and offers two products with the associated services which may be selected. Products are stored in the products-instance and list of all available services and sub-services is in the services-instance. There's also a button which allows you to add another product.

Now, all is well when the page is initially loaded - you can check or un-check services and the products-instance is correctly updated. However, if you try to add another product (thus modifying the products-instance's list of "product" nodes) a client-side code exception will occur saying "Cannot call method 'getRoot' of undefined".

Orbeon engine version is TAG_OPS_3_8_0_201005141856.

Thanks in advance,
Miro

test.xhtml