TransactionManager fields to protected?

I would like to extend TransactionManager and override the method:

     protected void initParticipants (Element config)
         throws ConfigurationException
     {
	......
     }

I want to do this in order to init my participants in a special way.  
Unfortunately the "groups" field is not "protected" and there are no  
accessor methods so it does not matter that I can override  
initParticipants method. Would it be possible to change the fields on  
TransactionManager to "protected"?

-Anthony

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