Connect to MWS from JavaService to retrieve information

Greetings,

I have a really strange task. I’m developing a solution to list users within our WebMethods Architecture. Our users however are registered in MWS and in IS Central User Management is configured appropriately. Is there a way to connect to MWS and possibly retrieve a user list from an IS JavaService?
I tried the wmroot userList service, but it only returns local users which does not contain the users I’m interested in. I want to list the non-local users.

thanks for all your tips!