TWO Outlook Calendars: Evnts don't Synch to both?

[dmg741]

I use a Blackberry Curve 8530. I synch it with the Outlook Calendar at home, (my primary calendar), AND with my Outlook calendar at work, (both Outlook 2007).
After synching with the Work calendar, some events don't get copied. On the Home calendar, everything Synchs just fine.
I can manually enter the event on the Work calendar, and when I re-synch, of course I wind up with two events on the Blackberry.

I guess I'm wondering why an event would synch on one calendar and not another.