error starting wsadmin.sh script in websphere 5.0.2 aix

[Alpha]

I am able to start the application server fine. and can use the admin
console fine. I wanted to use the wsadmin tool, but everytime I run
the wsadmin.sh on aix or wsadmin.bat on windows, I get the following
error. What am I doing wrong. Any help would be greatly appreciated.
Thanks. Also, I am using the base application server and not the
network deployment option. I use the startserver.sh server1 command
to start the app server.

Error:

$./wsadmin.sh
java.lang.reflect.InvocationTargetException:
java.lang.reflect.UndeclaredThrowableException: [SOAPException:
faultCode=SOAP-ENV:Server.Exception; msg=ADMC0011E: SOAP RPC call can
not be unmarshalled;
targetException=java.lang.IllegalArgumentException: Unable to resolve
namespace URI for 'ns1'.]
at com.ibm.ws.management.connector.soap.SOAPConnectorClient.handleAdminFault(SOAPConnectorClient.java:505)
at com.ibm.ws.management.connector.soap.SOAPConnectorClient.invokeTemplate(SOAPConnectorClient.java:474)
at com.ibm.ws.management.connector.soap.SOAPConnectorClient.invoke(SOAPConnectorClient.java:382)
at com.ibm.ws.management.connector.soap.SOAPConnectorClient.invoke(SOAPConnectorClient.java:207)
at $Proxy0.invoke(Unknown Source)
at com.ibm.ws.management.AdminClientImpl.invoke(AdminClientImpl.java:162)
at com.ibm.ws.scripting.CommonScriptingObject.connectToAdminService(CommonScriptingObject.java:125)
at com.ibm.ws.scripting.CommonScriptingObject.<init>(CommonScriptingObject.java:99)
at com.ibm.ws.scripting.AdminControlClient.<init>(AdminControlClient.java:149)
at com.ibm.ws.scripting.AbstractShell.createControlClient(AbstractShell.java:823)
at com.ibm.ws.scripting.AbstractShell.run(AbstractShell.java:1379)
at com.ibm.ws.scripting.WasxShell.main(WasxShell.java:770)
at java.lang.reflect.Method.invoke(Native Method)
at com.ibm.ws.bootstrap.WSLauncher.main(WSLauncher.java:94)