C/ALM Traceability Queries for custom OSLC Provider

Hi,

I am implementing my own OSLC Provider and use RTC as a client / OSLC Consumer. This works quite fine so far (after implementing the rootservices, which is not part of OSLC) and I can link Work Items from RTC to Change Requests in my OSLC Provider.

When enabling a RTC project to link against another OSLC project from my Provider, the folder C/ALM Traceability Queries appears in the Work Items tab, including a query "Open defects related to open change requests".

Executing this query results in a message:

Error!
Host name may not be null

I recognized that RTC accesses the OSLC cm service document, but does not seem to be happy with the one I provide.

What is RTC trying to access here? I did not find any documentation about this feature.

Thanks a lot,
Timo