PortableRemoteObject problem with JDK 1.3 and weblogic

I am getting a ClassCastException when I try to cast a weblogic 
container-managed
entity bean's findAll() return type (Enumeration) via
PortableRemoteObject.narrow(), 

	Enumeration e = (Enumeration) PortableRemoteObject.narrow
(home.findAll(),
		A.class)
where home is the home interface for class A, i. e.,
	AHome home = (AHome) PortableRemoteObject.narrow ... //Note 
this line runs fine.

The stack traces shows that javax.rmi.PortableObject.narrow is 
calling 
com.sun.corba.se.internal.javax.rmi.PortableRemoteObject.narrow which 
throws
the ClassCastException.

The same code used to work with weblogic 5.1 and HP's JDK 1.2. I got 
this
exception when we compiled the code under 1.2 and run it under JDK 
1.3 with same weblogic.
(I personnally do not like the idea of compiling and running on 
different JDKs, but
that is someone else's "great" idea and I have no control over it)

After looking into the contents of Jar files, I think here is what is 
happening.
Since JDK 1.2 does not include javax.rmi and weblogic does come with 
its own javax.rmi,
I think we must have been using weblogic's implementation of 
javax.rmi when we use JDK 1.2.
Now that we have switched to JDK1.3 which comes with its own 
javax.rmi, JVM must be
using JDK 1.3's javax.rmi and that is why you see the trace with 
SUN's internal
implementation throwing out exceptions. 

So the issue appears to be that we have two different and 
incompatible javax.rmi 
implementation, one from SUN and one from weblogic. 

Here are my questions:

1. Is it legal to do a narrow from Enumeration type ? If yes, then is 
this a bug in JDK1.3 ?

2. I think I can get around this problem by narrowing one enumeration 
element at a time, but
I prefer not to do that. The other approach is to somehow tell JVM to 
use weblogic's 
javax.rmi.PortableRemoteObject implementation via system properties (-
D flag). 
However, I can not find any weblogic system properties to do that. 
Does anyone know how to
do this ? If I can not do this, I think my last resort is to use -
Xbootclasspath to 
tell JVM to load weblogic's classes before JDK's classes.

I would appreciate any comments/suggestions on my problem.

Thanks.

Peter