Start j2ee server - NoClassDefFoundError - Please help!

[Venky Srinivasan]

I installed j2ee1.3.1 and tried starting j2ee server. I got the below exception:
Exception in thread "main" java.lang.NoClassDefFoundError: org/omg/CosNaming/NamingContextOperations

at java.lang.ClassLoader.defineClass0(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:460)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:111)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:247)
at java.net.URLClassLoader.access$100(URLClassLoader.java:55)
at java.net.URLClassLoader$1.run(URLClassLoader.java:194)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:187)
at java.lang.ClassLoader.loadClass(ClassLoader.java:288)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:286)
at java.lang.ClassLoader.loadClass(ClassLoader.java:244)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:304)
at com.sun.corba.ee.internal.corba.ORB.<init>(ORB.java:310)
at com.sun.corba.ee.internal.iiop.ORB.<init>(ORB.java:94)
at com.sun.corba.ee.internal.POA.POAORB.<init>(POAORB.java:125)

My environ variables:
classpath=C:\jdk1.3\lib;.;C:\j2sdkee1.3.1\lib\j2ee.jar;
path=C:\jdk1.3\bin;C:\j2sdkee1.3.1\bin;
J2EE_HOME=c:\j2sdkee1.3.1
JAVA_HOME=c:\jdk1.3

Why am I getting this exception? Please help?