ABAP + J2EE System wants to use User database from other R/3 system

I have installed WAS 640 ABAP + J2EE system and installed EP 6.0 SP11 on that. I want to use the user data from other R/3 system.

Please advise, how to configure this scenerio. Earlier I have installed only J2EE and EP 6.0 and configured R/3 system in data source management and it worked fine.

Appreciate your input.

Thanks,

Digesh