mine was not always updating the way it should...and it even started to wreck my berry up (8310). I buddy a mine who I work with (we work at att) said that he had to call Tech service for a customers berry and they found it had the Facebook app....
uninstalled the Facebook App..pulled the battery...phone was cured lol...same deal for me...I couldn't make calls out of nowhere....i didn't have this problem with FB 1.5 but with 1.6 i've had issues...
A solution to FB 1.6 and why the events don't show on my BB
calendar. The contacts that are on your facebook account need to
be connected to your BB in order for birthdays to appear.
Open FB 1.6, click on friends, hit BB icon menu, then click on
connect to blackberry contact.
every now and then mine will malfuntion. i either do a battery pull or master radio reset. if that doesn't work i just blame facebook and go without for a day or two - you know that is an option, right? :-)