No, actually, it's not a matter of vice versa. It's a mostly one-way relationship.
It's OK (just suboptimal) for non-equal objects to have equal hashcodes.
There's no other way around wild-card matching than to ignore any wildcard matchable attribute in the hashcode.

There MAY be issues with the equals and hashCode as they originally existed -- we've recently patched them -- that caused one of the conflicts I found.