Does anyone know whether it is possible to implement a hierarchical navigation bar in Mediawiki like e.g.:

* CASES ** BUSINESSCASES-URL | BUSINESSCASES *** BCASE1-URL | CASE1 *** BCASE2-URL | CASE2 ** TECHNICALCASES-URL | TECHNICALCASES *** TCASE1-URL | CASE1 *** TCASE2-URL | CASE2

Has somebody experience with this?

Thanks in advance for any help!