@Override
    public void printStackTrace(PrintWriter pw) {
        super.printStackTrace(pw);
        if (nestedThrowable != null) {
            nestedThrowable.printStackTrace(pw);
        }
    }
Exception used for representing a conflict error in a MUCRoom. There are many reasons why a 
conflict error could occur such as: owner tries to remove all the owners of a room. A 409 error
code is returned to the user that requested the invalid operation.

@author Gaston Dombiak
xmppserver/src/main/java/org/jivesoftware/openfire/muc/ConflictException.java