securing template1

How do i prevent ordinary users from altering the template1 database,
eg they can create tables in template1;

revoke doenst do the trick,
template1 remains visible and a user can create table in template1 using
  for example pgadmin

select * from pg_database where datname like '%temp%';


datname    | datdba | encoding | datistemplate | datallowconn |
datlastsysoid | datvacuumxid | datfrozenxid | datpath | datconfig |
      datacl

---------------+--------+----------+---------------+--------------+---------------+--------------+--------------+---------+-----------+--------------------------
  template1     |      1 |        6 | t             | t            |
      17140 |      4628963 |   3225854436 |         |           |
{postgres=C*T*/postgres}
  template0     |      1 |        0 | t             | f            |
      17140 |          464 |          464 |         |           |
{postgres=C*T*/postgres}
  ouwetemplate1 |      1 |        0 | t             | t            |
      17140 |      4623413 |   3225848886 |         |           |
{postgres=C*T*/postgres}
(3 rows)


tnx,