Problemas instalando oracle 10 en debian

[roscar]

Buenas,

estoy intentando instalar oracle 10g express edition en debian. Lo instalo perfectamentr, pero a la hora de intentar acceder con sql plus me da el siguiente error:

ORA-01034 oracle not available
ORA-27121 unable to determine size of shared memory segment

AL hacer el lsnrctl status, me dice que la instancioa está loqueada, esto es lo que obtengo:


LSNRCTL for Linux: Version 10.2.0.1.0 - Production on 21-MAY-2009 01:46:45

Copyright (c) 1991, 2005, Oracle. All rights reserved.

Welcome to LSNRCTL, type "help" for information.

LSNRCTL> status
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC_F OR_XE)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 10.2.0.1.0 - Production
Start Date 21-MAY-2009 00:54:32
Uptime 0 days 0 hr. 52 min. 24 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Default Service XE
Listener Parameter File /usr/lib/oracle/xe/app/oracle/product/10.2.0/server/network/admin/listener.ora
Listener Log File /usr/lib/oracle/xe/app/oracle/product/10.2.0/server/network/log/listener.log
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC_F OR_XE)))
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=segucert )(PORT=1521)))
Services Summary...
Service "PLSExtProc" has 1 instance(s).
Instance "PLSExtProc", status UNKNOWN, has 1 handler(s) for this service...
Service "XE" has 1 instance(s).
Instance "XE", status BLOCKED, has 1 handler(s) for this service...
Service "XE_XPT" has 1 instance(s).
Instance "XE", status BLOCKED, has 1 handler(s) for this service...
The command completed successfully
LSNRCTL> Instance "XE", status BLOCKED, has 1 handler(s) for this service


¿Me puede decir alguien como activar la instancia?He intentado buscar el comando dbstart pero no lo encuentro en el bin del oracle_home

Gracias