Step 7 of the initialization process in 5.5 states (emphasis mine):

"Next, if C is a class rather than an interface, *and its superclass has not yet been initialized*, then let SC be its superclass and let SI1, ..., SIn be all superinterfaces of C (whether direct or indirect) that declare at least one non-abstract, non-static method."

In the case in which the superclass has been initialized but a superinterface has not, this is incorrect. The superinterface should be initialized anyway.