UML14 — UML 1.1 issue on Associations

Summary: The semantics of Navigation with Nary associations is not clear. For example, If we have three Classes C1, C2, C3 linked with a ternary association.
If this ternary association is navigable to C3 : what does it means?? Does C1 and C2 instances may access to C3 linked instances through this association?
Then if the ternary association is navigable to C2 and to C3. Is this legal? What does it means? Does C1 instances may access to C2 and C3 instances? Does C2 instances may access to C3 instances and C3 instances may access to C2 instances?
Some clarification is needed there.
I imagin that Navigability makes sense in binary association, but do not make much sense with Nary associations.

Clarified in UML 1.3.