However this doesn't mean
    that there should be a separate ticket for each change.

      <ul>
        <li>If a change is made to the trunk and then a bug is subsequently
        found then, if this happens before the next release of the system, the
        subsequent change can be recorded on the same ticket.</li>

        <li>There can often be changes which don't really affect the system
        itself since they are just system administration details. One way of
        dealing with this is to open a