Oracle Database Discussions

Hi,
in 10g R2 on Linux, I'm following note 374069.1 to create standby instance on another host. But when executing :

export ORACLE_SID=proddb
rman target sys/pwd@proddb auxiliary /
connected to target database: PRODDB (DBID=355765605)
connected to auxiliary database (not started)

RUN {
2> allocate channel C1 device type disk;
3> allocate auxiliary channel C2 device type disk;
4> duplicate target database for standby nofilenamecheck;
5> }


I receive :

RMAN-04006: error from auxiliary database: ORA-01034: ORACLE not available.

but from :
lsnrctl services :
Service "proddb" has 1 instance(s).
Instance "AUX", status BLOCKED, has 1 handler(s) for this service...

Any idea ??

I have launched AUX like this :
$ export ORACLE_SID=AUX
$ sqlplus '/ as sysdba'
SQL> startup nomount;

Many thanks.