SAP NetWeaver server appends extra parameter (saplb) with jsessionid when rewriting url (session management).
When I start my ZK application on NW, application does not work because ZK tried load malformed URLs:
Problem is in: https://github.com/zkoss/zk/blob/master/zk/src/archive/web/js/zk/zk.js#L1233 when ZK doesn't expected multiple session parameters in url (it search for last position of ';').