Hi Kevin,
It is possible to make logon group based load balancing work for Java servers. In addition the Java server configuration, it is necessary to configure the web dispatcher properly for this to work. For details, please refer to note 1127717 and the online documentation,
http://help.sap.com/saphelp_nw73/helpdata/en/4a/93c8ceedaa388fe10000000a42189c/content.htm
Best regards,
Jun