final SecurityManager sm = context.getBroker().getBrokerPool().getSecurityManager();
final Account account = sm.getAccount(userName);
account.remGroup(groupName);
//TEMP - ESCALATE TO DBA :-(
//START TEMP - Whilst we can remove the group from the user
//we cannot update the user because we do not have sufficient permissions
//in the real world we should not be able to do either. The modelling of group