Does anybody know how to solve the following:

I have user/usergroup dimension (of snowflake type with 2 tables: for users and groups with 1 join by ID) and parent-child dimension for usergroup itself (on of usergroup may be subgroup of another)
I want to create one dimension for both usergroups/users, i.e. have content-based levels for usergroups and then users on the leafs, but I cannot find the way in MSSQL Analysis Server to do this.

Thanks in advance,