Oracle Application Server issue

Strange error in Oracle Application Server 10g 10.1.3.3.

I have tried to start it using opmnctl startall and it finish with following error:

10/03/25 08:06:44 WARNING: OC4J will not send ONS ProcReadyPort messages to opmn for service: OC4JServiceInfo id: null protocol: jms hostname: nul
l port: 12602 description: null
10/03/25 08:06:44 null hostname was null
10/03/25 08:06:44 Oracle Containers for J2EE 10g (10.1.3.3.0)  initialized

First idea was that something is wrong with /etc/hosts file or IP has been changed but everything was OK. I have found solution on OTN forum and it works. You have to stop all iAS components and delete all files from following directories:

$ORACLE_HOME/j2ee/home/persistence
$ORACLE_HOME/j2ee/[other OC4J]/persistence

regards,

Marcin