ORA-12523 when doing startup after shutdown

Hi,

when I needed to change an initialization parameter not changable using ALTER SYSTEM (like utl_file_dir), I always did the following:

connect sys/...@alias as sysdba

create pfile='.....\init.ora' from spfile;

<modify init.ora, add the parameter>

shutdown immediate

create spfile from pfile='.....\init.ora'

startup

Now (11.2.0.1) I observe that I get "ORA-12523: TNS:listener could not find instance appropriate for the client connection"  when issuing startup.

The instance is registered with the listener, but is in the state UNKNOWN at the moment.

If I exit, set ORACLE_SID and do the folowing (I'm using the bequeath protocol in this case, aren't I)