I've been testing migrations of our Moodle installation and I've noticed each time that the role field for database enrolments (enrol_db_remoterolefield) isn't being mapped into the correct value upon upgrade (enrol_database | remoterolefield). I believe (but have not tested) that this is because:

if (isset($CFG->enrol_remoterolefield)) {

    set_config('remoterolefield', $CFG->enrol_remoterolefield, 'enrol_database');

    unset_config('enrol_remoterolefield');

}

should be using $CFG->enrol_db_remoterolefield instead. I am using the most up-to-date version of the MOODLE_21_STABLE branch available on github. Please forgive me if this report is in error

Replication instructions:

• Upgrade a Moodle 1.9 installation using database enrolments with roles defined to Moodle 2.0
• The remoterolefield is empty after upgrade.