Restricted Access to other schemas

Hi,
i have added a new Schema in our Oracle 10.2.0.4 Database:

Create Tablespace $TSNAME$ Datafile '$DBPATH$\$TSNAME$.dbf' Size 1000M autoextend on next
200M;

create user $DBUSER$ identified by $PASSWD$;
alter user $DBUSER$ default tablespace $TSNAME$;

grant create view to $DBUSER$;
grant connect to $DBUSER$;
grant resource to $DBUSER$;

grant select any table to $DBUSER$;
grant insert any table to $DBUSER$;
grant delete any table to $DBUSER$;


So everything works fine so far. But I can access other schemas too. That should not be.

Found something but this doesn´t work:

Begin
  For i in (select owner, table_name from dba_tables where owner not like '%SYS%')