java.io.UTFDataFormatException --- ORION1.5.2

[mohan krishna]

Hello Everybody,

Orion1.3.8 is the current version of ORION we are using at this moment.
Now we upgraded the older version with version 1.5.2.
When i start the service of ORION it throws the following Exception ...

java.io.UTFDataFormatException
        at java.io.DataInputStream.readUTF(Unknown Source)
        at java.io.DataInputStream.readUTF(Unknown Source)
        at com.evermind._ek._hy(Unknown Source)
        at com.evermind._cv._hy(Unknown Source)
        at com.evermind._cyb.run(Unknown Source)
        at java.lang.Thread.run(Unknown Source)

even though i change the server.xml by removing the "principals" tag.
JDK1.3.1 is being used with ORION ...

Any suggestions ... 

Mohan Krishna