Multiplicity 1.21 post upgrade issue

I just upgraded to 1.21 the other day and since then I've noticed an issue with the primary machine. I run my main desktop with 2 secondaries, one on either side. After the screen saver has kicked in on my primary I seem to lose my mouse pointer. The mouse is still active, if I move from primary to secondaries the mouse works and shows up on secondaries, and it's actually there on the primary as I can mouse over icons and see them highlight and click/double-click/left-click etc. and all work. There's just no visible pointer.