One of our local tools is listening for sakai_events referring to Sections.

when a section is manually added, this code:

// Save the site, along with the new section
try {
siteService().save(site);
for(Iterator<CourseSection> iter = sections.iterator(); iter.hasNext();) {
postEvent("section.add", iter.next().getUuid());
}
return addedSections;
} catch (IdUnusedException ide) {
log.error("Error saving site... could not find site " + site.getId(), ide);
} catch (PermissionException pe) {
log.error("Error saving site... permission denied for site " + site.getId(), pe);
}
return null;

posts the event section.add for the new section, but the REF field is always NULL.

The sections object used in the iterator contains sections w/out uuids.

Solution:
Change the object iterated to addedSections and the sakai_event table entry will get the correct value for REF, as this code intended.