Mouse Pointer/Arrow disappears - Latitude Xt

I've had this Latitude XT tablet since late summer 2008. It is a fantastic little computer. Since getting it, though, I have had one annoying issue. Every once in a while, the mouse pointer/arrow will disappear. I am 90% sure it has something to do with the capacitive touchscreen, because if I move around using the trackpad sometimes the invisible pointer turns into the dot that should be there when I am using the tablet's stylus. Physically touching the screen (again, it's capacitive so this is the equivalent of a click) and then moving around with the trackpad makes the arrow/pointer come back. This problem has occurred in Windows XP, Vista, and Windows 7 (which I installed on to the computer myself). It happens with or without NTrig installed (I am not currently using the computer with NTrig because I have no need for the options/features it adds). I know this is not a widespread problem, and I know this is not a particularly popular computer, but I was wondering if anyone could shed some light on this. Thanks.