problem with dbca on Oracle 9i R2 9.2.0.1.0 Linux

When I want to start dbca on my installation I get Java errors below:

System is a RH 2.1 AS.

$ dbca
Exception in thread "main" java.lang.NullPointerException

        at oracle.sysman.assistants.util.NetworkUtils.getOneLocalListenerProtocolAddress(NetworkUtils.java:1897)
        at oracle.sysman.assistants.util.NetworkUtils.getOneLocalListenerProtocolAddress(NetworkUtils.java:1962)
        at oracle.sysman.assistants.util.NetworkUtils.getOneLocalListenerProtocolAddress(NetworkUtils.java:1954)
        at oracle.sysman.assistants.util.NetworkUtils.getOneLocalListenerProtocolAddress(NetworkUtils.java:1946)
        at oracle.sysman.assistants.util.NetworkUtils.getOneLocalListenerProtocolAddress(NetworkUtils.java:1863)
        at oracle.sysman.assistants.util.NetworkUtils.getLocalListenerAddress(NetworkUtils.java:736)
        at oracle.sysman.assistants.util.NetworkUtils.getLocalListenerAddresses(NetworkUtils.java:774)
        at oracle.sysman.assistants.util.NetworkUtils.needLocalListener(NetworkUtils.java:712)
        at oracle.sysman.assistants.util.step.StepContext.setListenersToUpdate(StepContext.java:485)
        at oracle.sysman.assistants.util.step.StepContext.<init>(StepContext.java:139)
        at oracle.sysman.assistants.dbca.backend.Host.<init>(Host.java:454)
        at oracle.sysman.assistants.dbca.ui.UIHost.<init>(UIHost.java:185)
        at oracle.sysman.assistants.dbca.ui.InteractiveHost.<init>(InteractiveHost.java:54)
        at oracle.sysman.assistants.dbca.Dbca.getHost(Dbca.java:141)
        at oracle.sysman.assistants.dbca.Dbca.execute(Dbca.java:85)
        at oracle.sysman.assistants.dbca.Dbca.main(Dbca.java:161)

I have tried "touch /etc/rac_on" solution mentioned in another thread on comp.databases.oracle. dbca uses JRE1.1.8. I have also tried to use 1.3.1 comes with oracle installation and also latest 1.3.1 JDK. Error was same.
I think this is a OS network issue, However I can not find anything. My hostname/IP configuration is set correctly. Anybody have an idea?

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