Error when deploy two beans have same names!

[changemylife]

Hi all!
I use jboss-4.0.5.GA and EJB3.0
I write two beans that have same name (called BeanA). Example:

Inside package: my.com has a bean called BeanA and exported to "my.jar"
Inside package: john.com has a bean called Bean A and exported to "john.jar"

I deployed two jars follow order: my.jar is first, and john.jar is second. Deploying two jars (my.jar and john.jar) is Ok!
On the client side, I write two clients. Client1 use my.jar and client2 use john.jar

import my.com.BeanA;
...
Context ctx = new InitialContext();
BeanA b = (BeanA)ctx.lookup(BeanABean/remote);
b.add(1,2);

---> all works are ok!

But on the Client2:

import john.com.BeanA;
..
Context ctx = new InitialContext();
BeanA b = (BeanA)ctx.lookup(BeanABean/remote);
b.add(1,2);

And then, Client2 received error :

Exception in thread "main" java.lang.ClassCastException: $Proxy0
 at client.ClientTest1.main(ClientTest1.java:18)

at line:

BeanA b = (BeanA)ctx.lookup(BeanABean/remote);

I think that my.jar is first deployed so my works are success! And JBoss not recognize john.jar when it deployed after, so my works are fail !
Have ideas about this problem? Please guide to me!
Thanks very much.