[CentOS] Korganizer Calendar Alarms stopped working

For a long time--years-- I've been using Korganizer's Calendar.  But 
lately-- since the last kernel upgrade, I believe-- the alarms don't 
work anymore.  I set an appointment and (most of the time) schedule an 
alarm (one or more) for it, but the small windows containing the 
reminders don't pop up anymore... not even those set a year ago which 
always worked before.

Anyone else experiencing this?  Anyone know what a fix for it might be?

tia,
ken