DBD::Multiplex and $dbh->{AutoCommit}

All -

I'm working on a rather large patch to DBD::Multiplex to make it
work correctly with a master/slave setup and transactions. In the
tests I've written, I've run into a very odd situation. I'm attempting
to trace what happens when $dbh->{AutoCommit} is executed. But,
DBD::Multiplex::db::FETCH isn't being executed. It is when I do a
$dbh->{RaiseError} and DBD::Multiplex::db::STORE is being executed
when I set $dbh->{AutoCommit}.

Does anyone have any idea why this might be?

Thanks,
Rob