Maintenance commands on standby servers

Hi,

Is it possible to run maintenance commands like ANALYZE, VACUUM, CLUSTER
on a standby server ?

The documentations says that those operations can not be done in
recovery mode, but that "some of these commands are actually allowed
during "read only" mode transactions on the primary" [1].

[1]
http://www.postgresql.org/docs/9.0/static/hot-standby.html#HOT-STANDBY-ADMIN

Regards.

--
Sylvain Rabot <sylvain@abstraction.fr>