The libjingle developer guide quite vaguely mentions the incompatibility between the libjingle implementation of the Jingle specification and XEP-0166. It also mentions that it is incompatible with XEP-0167, XEP-0176 and XEP-0177.
You should never dwell on these differences; in fact, it is not clear whether these differences are allowed.
What is the difference between XEP and libjingle implementation?
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